I've looked over the stackoverflow and the internet and I couldn't find a clear answer that helped me.
I have an assignment and it includes the following class, which is a GUI. I have Junit tested the other classes but for this I didn't know how.
import java.awt.*;
public class CruiseDisplay extends Canvas {
private int recorded = 0; //recorded speed
private boolean cruiseOn = false; //cruise control state
private final static int botY = 200;
private Font small = new Font("Helvetica",Font.BOLD,14);
private Font big = new Font("Helvetica",Font.BOLD,18);
public CruiseDisplay() {
super();
setSize(150,260);
}
Image offscreen;
Dimension offscreensize;
Graphics offgraphics;
public void backdrop() {
Dimension d = getSize();
if ((offscreen == null) || (d.width != offscreensize.width)
|| (d.height != offscreensize.height)) {
offscreen = createImage(d.width, d.height);
offscreensize = d;
offgraphics = offscreen.getGraphics();
offgraphics.setFont(small);
}
offgraphics.setColor(Color.black);
offgraphics.fillRect(0, 0, getSize().width, getSize().height);
offgraphics.setColor(Color.white);
offgraphics.drawRect(5,10,getSize().width-15,getSize().height-40);
offgraphics.setColor(Color.blue);
offgraphics.fillRect(6,11,getSize().width-17,getSize().height-42);
}
public void paint(Graphics g) {
update(g);
}
public void update(Graphics g) {
backdrop();
// display recorded speed
offgraphics.setColor(Color.white);
offgraphics.setFont(big);
offgraphics.drawString("Cruise Control",10,35);
offgraphics.setFont(small);
drawRecorded(offgraphics,20,80,recorded);
if (cruiseOn)
offgraphics.drawString("Enabled",20,botY+15);
else
offgraphics.drawString("Disabled",20,botY+15);
if (cruiseOn)
offgraphics.setColor(Color.green);
else
offgraphics.setColor(Color.red);
offgraphics.fillArc(90,botY,20,20,0,360);
g.drawImage(offscreen, 0, 0, null);
}
public void drawRecorded(Graphics g, int x, int y, int speed) {
g.drawString("Cruise Speed",x,y+10);
g.drawRect(x+20,y+20,50,20);
g.setFont(big);
g.drawString(String.valueOf(speed+20),x+30,y+37);
g.setFont(small);
}
public void enabled() {
cruiseOn = true;
repaint();
}
public void disabled() {
cruiseOn = false;
repaint();
}
public void record(int speed) {
recorded=speed;
repaint();
}
}
Can somebody help me please?
Related
Full error is "NullReferenceException: Object reference not set to an instance of an object
battery.OnTriggerStay (UnityEngine.Collider other) (at Assets/battery.cs:32)"
heres my screen in case its something i didnt do in the inspector: http://imgur.com/a/wWSGJ
here is my code (not sure if you need my flashlight code too):
public class battery : MonoBehaviour {
public float a;
public float b;
public float c;
public float d;
public bool showText;
public int Bat;
public GameObject Flight;
public int mainBat;
public bool safeRemove;
void Start()
{
showText = false;
}
void OnTriggerStay(Collider other)
{
showText = true;
if (!safeRemove)
{
if (Input.GetKeyUp (KeyCode.E))
{
mainBat = Flight.GetComponent<flashlight> ().batLevel;
Bat = 20;
Flight.GetComponent<flashlight> ().batLevel = Bat +- mainBat;
safeRemove = true;
if (safeRemove)
{
Destroy (this.gameObject);
}
}
}
}
void OnTriggerExit(Collider other)
{
showText = false;
}
void OnGUI()
{
if (showText)
{
GUI.Box(new Rect(Screen.width/ 2.66f, Screen.height/ 3.48f, Screen.width/ 3.78f, Screen.height/ 16.1f), "Press 'E' to pick up");
}
}
}
I have been following this tutorial to learn how to implement Pinch Zoom and Pan capabilities into an app I am developing.
https://www.youtube.com/watch?v=BY8hLhu50po&list=PL9jCwTXYWjDJjDE_JxRozYGKGt8gbUXg7
Basically, he loads an image from the gallery and displays it in an image view that supports Zoom/Pan functionality.
I would like to preload an image into the image view rather than select one from the gallery. Ideally, I'd like to load an image from drawable.
The tutorial's app had a lot of extra features that I am trying to weed out.
First it opens a gallery. Then you select an image to display, and it displays it as a thumbnail inside of mImageView.
On Long Click, it hides mImageView and displays a maximized image inside of a second Image View. (MPinchZoomImageView)
At this point, the image supports zoom and pan functionality.
If I could, I'd like to skip the gallery and the first Image View and only use the PinchZoom Image View. I'm not sure how I'd do that.
Code:
ImageViewMainActivity
public class ImageViewMainActivity extends AppCompatActivity {
ImageView mImageView;
PinchZoomImageView mPinchZoomImageView;
private Uri mImageUri;
private static final int REQUEST_OPEN_RESULT_CODE = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_image_view_main);
mImageView = (ImageView) findViewById(R.id.imageView);
mPinchZoomImageView = (PinchZoomImageView) findViewById(R.id.pinchZoomImageView);
mImageView.setOnLongClickListener(new View.OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
pinchZoomPan();
return true;
}
});
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/*");
startActivityForResult(intent, REQUEST_OPEN_RESULT_CODE); // pass it a context of 0
}
#Override
public void onWindowFocusChanged(boolean hasFocus) {
super.onWindowFocusChanged(hasFocus);
View decorView = getWindow().getDecorView();
if(hasFocus) {
decorView.setSystemUiVisibility(
View.SYSTEM_UI_FLAG_LAYOUT_STABLE
| View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
| View.SYSTEM_UI_FLAG_FULLSCREEN
| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
| View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
);
}
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent resultData) {
if(requestCode == REQUEST_OPEN_RESULT_CODE && resultCode == RESULT_OK) {
if(resultData != null) {
mImageUri = resultData.getData();
Glide.with(this)
.load(mImageUri)
.into(mImageView);
}
}
}
private void pinchZoomPan() {
mPinchZoomImageView.setImageUri(mImageUri);
mImageView.setAlpha(0.f); // set mImageView invisible.
mPinchZoomImageView.setVisibility(View.VISIBLE);
}
}
PinchZoomImageView
public class PinchZoomImageView extends ImageView {
private Bitmap mBitmap;
private int mImageWidth;
private int mImageHeight;
private final static float mMinZoom = 1.f;
private final static float mMaxZoom = 4.f;
private float mScaleFactor = 1.f;
private ScaleGestureDetector mScaleGestureDetector;
private final static int NONE = 0;
private final static int PAN = 1;
private final static int ZOOM = 2;
private int mEventState;
private float mStartX = 0;
private float mStartY = 0;
private float mTranslateX = 0;
private float mTranslateY = 0;
private float mPreviousTranslateX = 0;
private float mPreviousTranslateY = 0;
private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {
#Override
public boolean onScale(ScaleGestureDetector detector) {
mScaleFactor *= detector.getScaleFactor();
mScaleFactor = Math.max(mMinZoom, Math.min(mMaxZoom, mScaleFactor));
// invalidate();
// requestLayout();
return super.onScale(detector);
}
}
public PinchZoomImageView(Context context, AttributeSet attrs) {
super(context, attrs);
mScaleGestureDetector = new ScaleGestureDetector(getContext(), new ScaleListener());
}
#Override
public boolean onTouchEvent(MotionEvent event) {
switch(event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
mEventState = PAN;
mStartX = event.getX() - mPreviousTranslateX;
mStartY = event.getY() - mPreviousTranslateY;
break;
case MotionEvent.ACTION_UP:
mEventState = NONE;
mPreviousTranslateX = mTranslateX;
mPreviousTranslateY = mTranslateY;
break;
case MotionEvent.ACTION_MOVE:
mTranslateX = event.getX() - mStartX;
mTranslateY = event.getY() - mStartY;
break;
case MotionEvent.ACTION_POINTER_DOWN:
mEventState = ZOOM;
break;
}
mScaleGestureDetector.onTouchEvent(event);
if((mEventState == PAN && mScaleFactor != mMinZoom) || mEventState == ZOOM) { // called under the condition that window is zoomed i
invalidate();
requestLayout();
}
return true;
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int imageWidth = MeasureSpec.getSize(widthMeasureSpec);
int imageHeight = MeasureSpec.getSize(heightMeasureSpec);
int scaledWidth = Math.round(mImageWidth * mScaleFactor);
int scaledHeight = Math.round(mImageHeight * mScaleFactor);
setMeasuredDimension(
Math.min(imageWidth, scaledWidth),
Math.min(imageHeight, scaledHeight)
);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.save();
canvas.scale(mScaleFactor, mScaleFactor);
// canvas.scale(mScaleFactor, mScaleFactor, mScaleGestureDetector.getFocusX(), mScaleGestureDetector.getFocusY());
if((mTranslateX * -1) < 0) {
mTranslateX = 0;
} else if ((mTranslateX * -1) > mImageWidth * mScaleFactor - getWidth()) {
mTranslateX = (mImageWidth * mScaleFactor - getWidth()) * -1;
}
if((mTranslateY * -1) < 0) {
mTranslateY = 0;
} else if ((mTranslateY * -1) > mImageHeight * mScaleFactor - getHeight()) {
mTranslateY = (mImageHeight * mScaleFactor - getHeight()) * -1;
}
canvas.translate(mTranslateX/mScaleFactor, mTranslateY/mScaleFactor);
canvas.drawBitmap(mBitmap, 0, 0, null);
canvas.restore();
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
}
public void setImageUri(Uri uri) {
try {
Bitmap bitmap = MediaStore.Images.Media.getBitmap(getContext().getContentResolver(), uri);
float aspecRatio = (float) bitmap.getHeight() / (float) bitmap.getWidth();
DisplayMetrics displayMetrics = getResources().getDisplayMetrics();
mImageWidth = displayMetrics.widthPixels;
mImageHeight = Math.round(mImageWidth * aspecRatio);
mBitmap = Bitmap.createScaledBitmap(bitmap, mImageWidth, mImageHeight, false);
invalidate();
requestLayout();
} catch (IOException e) {
e.printStackTrace();
}
}
}
XML
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="mobapptut.com.imageviewer.ImageViewMainActivity">
<ImageView
android:layout_width="200dp"
android:layout_height="150dp"
android:id="#+id/imageView"
android:layout_centerInParent="true" />
<mobapptut.com.imageviewer.PinchZoomImageView
android:visibility="invisible"
android:id="#+id/pinchZoomImageView"
android:layout_centerInParent="true"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
Thank You
I have a recyclerview with a header achieved by using two different element types. In my header there is an edit text which I want to use for filtering the nonheader elements of the list. Below is my current implementation, I have one concern and one problem with it.
My concern is that what I am doing in publishResults with the notifyItemRangeRemoved and notifyItemInserted is the wrong way to update the recycler view. I originally was doing notifyDatasetChanged but his would cause the header row to be refreshed too and the edit text to lose focus. What I really want is a way to refresh only the item rows and leave the header row untouched.
My current problem is that with the existing code if I scroll down too much the edit text looses focus. I want the edit text to keep focus even if I scroll to the bottom of the list.
The code used to use a ListView with setHeaderView and that worked somehow so there must be someway of achieving the goal just not sure what the trick with a recycler view is. Any help is much appreciated.
public class SideListAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> implements Filterable {
private static final int TYPE_HEADER = 0;
private static final int TYPE_ITEM = 1;
private final List<String> data;
public List<String> filteredData;
private HeaderActionListener headerActionListener;
public SideListAdapter(Context context, ArrayList<String> data, HeaderActionListener headerActionListener) {
this.data = data;
filteredData = new ArrayList<>(data);
this.context = context;
this.headerActionListener = headerActionListener;
}
#Override
public Filter getFilter() {
return new TestFilter();
}
static class SideListItem extends RecyclerView.ViewHolder {
LinearLayout baseLayout;
public SideListItem(View itemView) {
super(itemView);
baseLayout = (LinearLayout) itemView.findViewById(R.id.settings_defaultcolor);
}
}
class SideListHeader extends SideListHeader {
EditText sort;
public SideListHeaderLoggedIn(View itemView) {
super(itemView);
sort = (EditText) itemView.findViewById(R.id.sort);
}
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == TYPE_ITEM) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item, parent, false);
return new SideListItem(v);
} else if (viewType == SideListHeader) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.header, parent, false);
return new SideListHeader(v);
}
throw new RuntimeException("there is no type that matches the type " + viewType + " + make sure your using types correctly");
}
public interface HeaderActionListener {
boolean onSortEditorAction(TextView arg0, int arg1, KeyEvent arg2);
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position) {
if (holder instanceof SideListHeader) {
final SideListHeader sideListHeader = (SideListHeader) holder;
sideListHeader.sort.setOnEditorActionListener(new TextView.OnEditorActionListener() {
#Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
}
});
sideListHeader.sort.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence charSequence, int i, int i2, int i3) {
}
#Override
public void onTextChanged(CharSequence charSequence, int i, int i2, int i3) {
}
#Override
public void afterTextChanged(Editable editable) {
String result = sideListHeader.sort.getText().toString().replaceAll(" ", "");
getFilter().filter(result);
}
});
}
if (holder instanceof SideListItem) {
// Inflate normal item //
}
}
// need to override this method
#Override
public int getItemViewType(int position) {
if (isPositionHeader(position)) {
return TYPE_HEADER;
}
return TYPE_ITEM;
}
private boolean isPositionHeader(int position) {
return position == 0;
}
//increasing getItemcount to 1. This will be the row of header.
#Override
public int getItemCount() {
return filteredData.size() + 1;
}
private class TestFilter extends Filter {
#Override
protected FilterResults performFiltering(CharSequence constraint) {
FilterResults results = new FilterResults();
String prefix = constraint.toString().toLowerCase();
if (prefix.isEmpty()) {
ArrayList<String> list = new ArrayList<>(data);
results.values = list;
results.count = list.size();
} else {
final ArrayList<String> list = new ArrayList<>(data);
final ArrayList<String> nlist = new ArrayList<>();
for (int i = 0 ; i < list.size(); i++) {
String item = list.get(i);
if (item.contains(prefix)) {
nlist.add(item);
}
}
results.values = nlist;
results.count = nlist.size();
}
return results;
}
#SuppressWarnings("unchecked")
#Override
protected void publishResults(CharSequence constraint, FilterResults results) {
notifyItemRangeRemoved(1, getItemCount()-1);
filteredData.clear();
filteredData.addAll((List<String>)results.values);
for(int i = 1; i < getItemCount() - 1; i++){
notifyItemInserted(i);
}
}
}
}
I'm not sure how correct this way is, but in my code I implemented it like that
private var headerList: List<HeaderItem> = listOf(HeaderItem("Title"))
private fun searchItem(items: List<Items>, query: String) {
items.filterIsInstance<MainItem>().filter { filteredItems ->
filteredItems.header.lowercase().contains(query.lowercase())
}.let { searchedItems ->
rvAdapter.submitList(headerList + searchedItems)
}
}
This way I was able to preserve header element when I did my search
I have a platformer class that creates a window and spawns platforms and a "character". It uses another class platform to make platforms. The character is supposed to jump up and land on the platforms. I use the getBounds and getTopY functions for collision detection but they only work for the first platform. How can i get them to work for multiple platforms?
public class Platformer extends JPanel {
Platform platform = new Platform(this);
Character character = new Character(this);
public Platformer() {
addKeyListener(new KeyListener() {
#Override
public void keyTyped(KeyEvent e) {
character.keyTyped(e);
}
#Override
public void keyReleased(KeyEvent e) {
character.keyReleased(e);
}
#Override
public void keyPressed(KeyEvent e) {
character.keyPressed(e);
}
});
setFocusable(true);
}
#Override
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
platform.Location(150,200);
platform.paint(g2d);
platform.Location(200,120);
platform.paint(g2d);
character.paint(g2d);
}
private void move(){
character.move();
}
public static void main(String args[]){
JFrame frame = new JFrame("Mini Tennis");
//create new game
Platformer platformer = new Platformer();
//add game
frame.add(platformer);
//size
frame.setSize(400, 400);
frame.setVisible(true);
//set close condition
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
while (true) {
platformer.move();
platformer.repaint();
try {
Thread.sleep(10);//sleep for 10 sec
} catch (InterruptedException ex) {
Thread.currentThread().interrupt();
}
}
}
}
public class Platform {
private static final int Height = 10;
private static final int Width = 60;
int x;
int Y;
private Platformer platformer;
public Platform(Platformer platformer) {
this.platformer = platformer;
}
public void Location(int xin, int yin) {
x = xin;
Y = yin;
}
public void paint(Graphics2D g) {
g.fillRect(x, Y, Width, Height);
}
public Rectangle getBounds() {
return new Rectangle(x, Y, Width, Height);
}
public int getTopPlat() {
return Y;
}
}
Actually you have only one platform. And you draw this platform twice in different places (paint function in Platformer):
platform.Location(150,200);
platform.paint(g2d);
platform.Location(200,120);
platform.paint(g2d);
Therefore I suppose you handle only one platform (with coordinates 200 and 120). You must keep all of your platforms and handle each of them separately.
I'm trying to make a small square move across the top of the panel. I'm not worried about the seamlessness of the animation or flicker or anything like that. It appears that in the while-loop, repaint() isn't repeatedly calling the paintComponent. Thoughts?
public class NodeMove extends JFrame {
boolean running = true;
public NodeMove() {
widgetNode panel = new widgetNode();
add(panel);
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400, 400);
setVisible(true);
Runnable node = new widgetNode();
Thread thread1 = new Thread(node);
thread1.start();
}
class widgetNode extends JPanel implements Runnable {
private static final long serialVersionUID = 1L;
private int x = 30;
private int y = 30;
public widgetNode() {
}
public void run(){
while(running){
nodeUpdate();
repaint();
try {
Thread.sleep(500);
} catch (InterruptedException e) {}
}
}
public void nodeUpdate(){
x += 4;
}
protected void paintComponent(Graphics g) {
super.paintComponents(g);
g.drawRect(x, y, 30, 30);
}
}
public static void main(String[] args) {
NodeMove frame = new NodeMove();
for(int i = 0; i < 50; i++){
frame.repaint();
}
}
}