I have an array of urls of images, from which i have to first download the images then show in sliding.
But i want to download images asynchronously. I am using 3 images at a time like in the below code :
var imageViewArray = [];
var nextImageIndex;
var imageNameArray=[];
for (var i = 0; i < 3; i++) {
var imageView1 = Titanium.UI.createImageView({
});
imageViewArray[i] = imageView1;
}
var scrollingView = Titanium.UI.createScrollableView({
views : imageViewArray,
width : 310,
height : 450,
top : 5,
left : 5,
borderWidth : 2,
borderColor : '#000'
});
scrollingView.addEventListener('scroll', function(e) {
Ti.API.info("C=" + e.currentPage);
Ti.API.info("N=" + nextImageIndex);
if (e.currentPage == 2 && nextImageIndex < imageNameArray.length - 2) {
//Setting the current page to 1 will allow the smooth swipe functionality
scrollingView.currentPage = 1;
nextImageIndex += 1;
var vw = scrollingView.views[0];
imageViewArray[0] = scrollingView.views[1];
imageViewArray[1] = scrollingView.views[2];
scrollingView.removeView[vw];
vw.image = imageNameArray[nextImageIndex + 1];
imageViewArray[2] = vw;
scrollingView.views = imageViewArray;
} else if (e.currentPage == 0 && nextImageIndex > 1) {
nextImageIndex -= 1;
scrollingView.currentPage = 1;
var vw = scrollingView.views[2];
imageViewArray[1] = scrollingView.views[0];
imageViewArray[2] = scrollingView.views[1];
scrollingView.removeView[vw];
vw.image = imageNameArray[nextImageIndex - 1];
imageViewArray[0] = vw;
scrollingView.views = imageViewArray;
}
});
scrollingView.views[0].image = imageNameArray[0];
scrollingView.views[1].image = imageNameArray[1];
scrollingView.views[2].image = imageNameArray[2];
nextImageIndex = 1;
Can anyone tell me where shall i need to download th eimages from the urls.
Thanks
Firstly, download at least 3 images to start with when you load this view. Then in your scroll event you'll download more images.
Q: Why are you removing views from the scrollview?
Related
I have a script that works mostly the way want. It looks at a cell then compares that to a column in another tab, finds the like items and returns that, and creates a dropdown on the cell. This moves down the column until it reaches the end. The problem is that it continues past the last row for about 20 rows. The starting row is row24.
function getInventoryItems() {
var jobSummaryInventoryItems = jobSummary.getRange(24, 8, jobSummary.getLastRow(), 1);
var jobSummaryInventoryItemsValues = jobSummaryInventoryItems.getValues();
var inventoryItems = inventory.getRange(4, 3, inventory.getLastRow(), 1);
var inventoryItemsValues = inventoryItems.getValues();
jobSummary.getRange(24, 8, jobSummary.getLastRow(), 1).setDataValidation(null);
for (z = 0; z < jobSummaryInventoryItemsValues.length; z++) {
if (jobSummaryInventoryItemsValues[z].toString().length > 1) {
var listOfInventory = [];
for (i = 0; i < inventoryItems.getLastRow() - 4; i++) {
if (inventoryItemsValues[i].toString() == jobSummaryInventoryItemsValues[z]) {
break;
}
var w = jobSummaryInventoryItemsValues[z];
if (inventoryItemsValues[i].toString().includes(jobSummaryInventoryItemsValues[z])) {
listOfInventory.push(inventoryItemsValues[i].toString());
}
}
}
if (listOfInventory.length > 0) {
var rangeRule = SpreadsheetApp.newDataValidation().requireValueInList(listOfInventory).build();
jobSummary.getRange(z + 24, 8).setDataValidation(rangeRule);
}
}
Get Inventory Items
function getInventoryItems() {
const ss = SpreadsheetApp.getActive();
const jobSummary = ss.getSheetByName('Job Summary');
const inventory = ss.getSheetByName('Inventory');
const jobSummaryInventoryItems = jobSummary.getRange(24, 8, jobSummary.getLastRow() - 23, 1);
const jobSummaryInventoryItemsValues = jobSummaryInventoryItems.getValues();
const inventoryItems = inventory.getRange(4, 3, inventory.getLastRow() - 3, 1);
const inventoryItemsValues = inventoryItems.getValues();
jobSummary.getRange(24, 8, jobSummary.getLastRow() -23, 1).setDataValidation(null);
for (z = 0; z < jobSummaryInventoryItemsValues.length; z++) {
if (jobSummaryInventoryItemsValues[z].toString().length > 1) {
let listOfInventory = [];
for (i = 0; i < inventoryItems.length; i++) {
if (inventoryItemsValues[i].toString() == jobSummaryInventoryItemsValues[z]) {
break;
}
let w = jobSummaryInventoryItemsValues[z];
if (inventoryItemsValues[i].toString().includes(jobSummaryInventoryItemsValues[z])) {
listOfInventory.push(inventoryItemsValues[i].toString());
}
}
}
if (listOfInventory.length > 0) {
let rangeRule = SpreadsheetApp.newDataValidation().requireValueInList(listOfInventory).build();
jobSummary.getRange(z + 24, 8).setDataValidation(rangeRule);
}
}
}
Sheet.getRange(row,column,number of rows, number of columns)
I have 13 images shown in page ,one of them is fixed and others changed depend on some data ,i made 12 if statement and it works ,but is there way to create one if statement with for loop like thus :
for (int i = 2; i >= 13; i++)
{
if (m_id >= i)
{
"image" + i.Source = ImageSource.FromFile("months" + i + ".png");
}
else
{
"image" + i.Source = ImageSource.FromFile("months"+i+"closed.png");
}
}
You should put all Images in an Array like
List<Image> Images = new List<Image>() {image2,image3,...,image13 };
And set the ImageSource like
for(int i=2;i<=13;i++)
{
Image image = Images[i - 2];
if (m_id >= i)
{
image.Source = ImageSource.FromFile("months" + i + ".png");
}
else
{
image.Source = ImageSource.FromFile("months"+i+"closed.png");
}
}
Problem Statement:
after updating fieldMappings and dataSet during runtime(After clicking on a button) for a stockgraph, validateNow() / validteData() is not plotting the graph.
Note: MACD0 is added from 25th element onward and expoSignalLine0 is added from 33rd element onward in the dataprovider and fieldMapping is also getting updated and can be verified same in console.enter code here
Following is the Code snippet:
(addMACD function is called on click of a button)
function addMACD() {
var chart = AmCharts.charts[ 0 ];
AmCharts.MACDGraphs = 0;
AmCharts.expoSignalLineGraphs = 0;
var MACDField = "MACD"+ AmCharts.MACDGraphs;
var expoSignalLineField = "expoSignalLine"+ AmCharts.expoSignalLineGraphs;
chart.dataSets[0].fieldMappings.push( {
fromField : MACDField,
toField : MACDField
},
{
fromField : expoSignalLineField,
toField : expoSignalLineField
});
var currClose;
var prevClose;
var twelveDayEMA =[];
var twentySixDayEMA =[];
var MACDarray = [];
var signalLineArray = [];
var MACDperiod = 9 ;// 9 day exponential average
for ( var i = 1; i < (chart.dataSets[0].dataProvider.length); i++) {
var dp = chart.dataSets[0].dataProvider[i - 1];
prevClose = parseFloat(dp["close"]);
var dp = chart.dataSets[0].dataProvider[i];
currClose = parseFloat(dp["close"]);
if( i==1){
twelveDayEMA[i] = (0.15*currClose) + (0.85*prevClose);
twentySixDayEMA[i] = (0.075*currClose) + (0.925*prevClose);
}
else{
twelveDayEMA[i] = (0.15*currClose) + (0.85*twelveDayEMA[i - 1]);
twentySixDayEMA[i] = (0.075*currClose) + (0.925*twentySixDayEMA[i - 1]);
}
if(i >= 25){
MACDarray[i] = twelveDayEMA[i] - twentySixDayEMA[i] ;
dp[MACDField] = MACDarray[i];
if(i == 25){
signalLineArray[i] = MACDarray[i];
}
else{
signalLineArray[i] = ( MACDarray[i]*(2/( MACDperiod + 1)) ) + ( signalLineArray[i - 1]*(1-(2/( MACDperiod + 1))) )
}
}
if(i >=33){
dp[expoSignalLineField] = signalLineArray[i];
}
}
console.log(chart);
if ( chart.panels.length == 1 || chart.panels.length == 2 || chart.panels.length == 3 || chart.panels.length == 4 || chart.panels.length == 5) {
var newPanel = new AmCharts.StockPanel();
newPanel.allowTurningOff = true;
newPanel.title = "MACD";
newPanel.showCategoryAxis = false;
graph1 = new AmCharts.StockGraph();
graph1.valueField = MACDField;
graph1.useDataSetColors = false;
graph1.lineColor="#6699FF";
graph1.title = "MACD";
newPanel.stockGraphs.push( graph1 );
graph2 = new AmCharts.StockGraph();
graph2.valueField =expoSignalLineField;
graph2.useDataSetColors = false;
graph2.lineColor = "#990000";
graph2.title = "MACD2";
newPanel.stockGraphs.push( graph2 );
var legend = new AmCharts.StockLegend();
legend.markerType = "none";
legend.markerSize = 0;
newPanel.stockLegend = legend;
chart.addPanelAt( newPanel, 1 );
chart.validateData();
chart.validateNow();
//chart.write("chartdiv");
}
}
You have to call validateNow first, then call validateData.
Alternatively, you can call validateNow(true, false) which has the same effect as calling the two functions separately.
Updated fiddle
I've deliberately provided the version number in the question as this is the kind of question that will go out of date at some point.
Here is a simple animation that will run perfectly smoothly in Chrome and Safari, but will be very jerky in Firefox:
function lerp(a,b,λ) {
return a + λ*(b-a);
}
function random(a,b) {
return lerp( a, b, Math.random() );
}
// = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
$(document).ready( function()
{
var canvas = document.getElementById("myCanvas");
var ctx = canvas.getContext("2d");
var balls = new Array(12);
for( var i=0; i<balls.length; i++ )
{
while(true)
{
var density = Math.sqrt( random(1,100) );
var r = random(5, 30);
var x = random( r+1, canvas.width-1 -(r+1) ),
y = random( r+1, canvas.height-1 -(r+1) );
var overlap = false;
for( var j=0; j<i; j++ )
{
var _x = balls[j].x - x,
_y = balls[j].y - y,
d2 = _x*_x + _y*_y,
_r = balls[j].r + r;
if( d2 < _r*_r )
overlap = true;
}
if( overlap )
continue;
balls[i] = {
color : d3.hsl( lerp(0,240,density/10), random(.3,.7), random(.3,.7) ).toString(),
x : x,
y : y,
vx : random(0, 0.2),
vy : random(0, 0.2),
r : r,
advance: function(t) {
this.x += t * this.vx;
this.y += t * this.vy;
}
};
break;
}
};
window.requestAnimationFrame(vsync);
var t_last;
function vsync(t)
{
if( t_last )
render( t - t_last );
t_last = t;
window.requestAnimationFrame(vsync);
}
function render(t_frame)
{
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
ctx.fillStyle="gray";
ctx.fillRect(0,0, canvas.width, canvas.height);
function advance_all(t) {
balls.forEach( function(b) {
b.advance(t);
});
}
var t_remaining = t_frame;
while(true) {
var hit = get_next_collision( balls, canvas.width, canvas.height );
if( t_remaining < hit.t )
break;
advance_all( hit.t );
t_remaining -= hit.t;
collide_wall( balls[hit.i], hit.wall );
balls[hit.i].advance(.001);
};
advance_all( t_remaining );
// draw balls
balls.forEach( function(ball) {
ctx.beginPath();
ctx.arc(ball.x, ball.y, ball.r, 0, Math.PI*2, true);
ctx.closePath();
ctx.fillStyle = ball.color;
ctx.fill();
});
}
});
// = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
function get_next_collision(balls,W,H)
{
var winner;
// ball-wall
balls.forEach( function(ball,i)
{
var t = [];
t['L'] = (ball.r - ball.x) / ball.vx; // s.x + t v.x = r
t['T'] = (ball.r - ball.y) / ball.vy;
t['R'] = (W-1-ball.r - ball.x) / ball.vx; // s.x + t v.x = (W-1)-r
t['B'] = (H-1-ball.r - ball.y) / ball.vy;
// get index of smallest positive t
var LR = t['L'] >= 0 ? 'L' : 'R',
TB = t['T'] >= 0 ? 'T' : 'B',
wall = t[LR] < t[TB] ? LR : TB;
if( ! winner || ( t[wall] <= winner.t ) )
winner = {
t : t[wall],
i : i,
wall: wall
};
});
return winner;
}
function collide_wall( A, wall )
{
if( wall == 'L' || wall == 'R' )
A.vx *= -1;
else
A.vy *= -1;
}
html, body {
width: 100%;
height: 100%;
margin: 0px;
}
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/mathjs/1.5.1/math.min.js"></script>
<script src="http://d3js.org/d3.v3.min.js"></script>
<canvas id="myCanvas">
<!-- Insert fallback content here -->
</canvas>
Why is Firefox performing significantly worse than its competitors?
If I take the number of balls to 500 Chrome is still smooth, Firefox is seriously choppy.
If I take the number of balls down to 1 Firefox is still burring it.
Another experiment I did was applying a fixed velocity increment each frame, so that the smoothness of the animation accurately reflects the evenness of the render callback. This showed Firefox to be all over the place. Chrome on the other hand was smooth.
If there is sufficient interest, I can provide a snippet for that also and maybe tidy up the first one so that it offers a slider to modify the ball count.
As far as I can see, (1) Firefox definitely isn't giving us a genuine VSYNC callback, I suspect it is just using a timer, (2) even correcting for that by manually calculating elapsed time for each frame, it burrs the animation, maybe suggesting that it sometimes the callback fires in time to catch the VSYNC and sometimes it misses the boat, (3) there is an additional compositing hit that is disproportionate compared with Chrome.
Is there anything to be done about this?
EDIT: I found this question from four years ago! Poor performance of html5 canvas under firefox -- please don't mark this question as the duplicate unless it is certain that the answer to that question is still the only relevant answer four years later. I've deliberately included the version number in the question, as the question pertains specifically to the current version.
I know the default icon is "circle",now I want to change the icon shape.The total icon shape are only "circle", "square", "triangle", "cross".Can Iuse custome icon?I use these codes in the databound event,but it seems not work.
var colorArr = new Array("#FF0000", "#FF8C00", "#006400", "#40E0D0", "#800080");
var iconShapeArr = newArray("circle", "square", "triangle", "cross");
function onDataBound(e) {
var chart = e.sender;
var series = chart.options.series;
for(var index = 0; index <= series.length - 1; index++) {
chart.options.series[index].color = colorArr[index];
chart.options.series[index].markers.background = colorArr[index];
// chart.options.series[index].notes.icon.shape = "square";
}
As far as I know,it can not be custom.You can change the type like these:
function onDataBound(e) {
var colorArr = ["#FF0000", "#FF8C00", "#006400", "#40E0D0", "#800080"];
var iconShapeArr = ["triangle", "square", "triangle", "cross"];
var chart = e.sender;
var series = chart.options.series;
for(var index = 0; index <= series.length - 1; index++) {
chart.options.series[index].color = colorArr[index];
chart.options.series[index].markers.background = colorArr[index];
chart.options.series[index].markers.type = iconShapeArr[index];
}
}