Nativescript page title not rendering when set after navigation - nativescript

I m bulding an app and i have a problem with rendering the title in the ActionBar after navigating to that page. Since the ActionBar cannot have an id i m using an observable viewModel in wich i set the title property.
-----xml-----
<Page.actionBar>
<ActionBar title="{{ name }}">
</ActionBar>
</Page.actionBar>
-------------
------js-----
exports.pageLoaded = function(args) {
page = args.object;
var navData = page.navigationContext;
viewModel.set("name",navData.name);
page.bindingContext = viewModel;
};
What i have seen so far debugging this problem is that when i close the phone screen and after that open it (refreshing the app) the action bar title will render.
Found the answer (a workaround) ,
<ActionBar>
<ActionItem ios.systemIcon="12" android.systemIcon="ic_menu_search" tap="showSearch" />
<ActionItem android.systemIcon="ic_menu_moreoverflow" tap="logout" text="Logout" android.position="popup" />
<ActionBar.titleView>
<StackLayout orientation="horizontal">
<Label text="{{ name }}" />
<Image src="res://app_icon" />
</StackLayout>
</ActionBar.titleView>

You need to set the title in a different page event, fairly certain you should do this in the navigatedTo event for the page.
For more info on the page navigation events, check out this blog post Nathanael Anderson - FluentReports - page navigating order of events

Related

NativeScript - Change Label into TextView/TextField with a Button

I am learning to make an app in NativeScript (Angular 2). In my item page, I want to have a button so that when I press it, I can change Label into TextView/TextField for editing the information of the item.
I know that I can use editable in TextView but I still want to know if it is feasible to have the button with that functionality. Thank you !!
item.component.html:
<StackLayout>
<Label class="h3" text="Name: {{ item.get_name() }}" textWrap="true">
</Label>
<Label class="h3" text="Credit: {{ item.get_credit() }}"></Label>
<Button class="btn" text="Edit" (tap)="change()"></Button>
</StackLayout>
<!-- After pressing the button -->
<StackLayout>
<TextView class="h3" [text]="item.get_name()" textWrap="true">
</TextView>
<TextView class="h3" [text]="item.get_credit()"></TextView>
<Button class="btn" text="Save" (tap)="change()"></Button>
</StackLayout>
This can be done in many ways, but one common way is by changing visibility of control and binding it to a variable / property in the code behind.
in your component html:
Then on your component ts or code-behind you can handle it in the change method:
class MyComponentSample {
isLabelMode: boolean = true; // Set to true if you want label to show by default or false if TextView as default
change() {
this.isLabelMode = !isLabelMode; // Basically you are toggling the mode here.
}
}

How to add an activity-indicator on a page level?

I would like to add an activity-indicator widget in my login page but I would like it to cover the whole screen, so I can prevent double click on the Login button.
Any idea, thanks!
If you wrap everything in a GridLayout, add a StackLayout as the last item in the row you want to cover. The StackLayout by default will cover the whole screen. Then you can show/hide via data. For example:
<GridLayout>
<StackLayout>
// All your page content goes here!
</StackLayout>
<StackLayout class="dimmer" visibility="{{showLoading ? 'visible' : 'collapsed'}}"/>
<GridLayout rows="*" visibility="{{showLoading ? 'visible' : 'collapsed'}}">
<ActivityIndicator busy="true" />
</GridLayout>
</GridLayout>
I have a "dimmer" StackLayout that I animate to be semi transparent black, then the Activity Indicator sits on top.
not sure what layout you have i will only put example(somehow simplified) from my project
Inside page u can put something like this, both StackLayout and ActivityIndicator are inside GridLayout which takes whole size of page
<GridLayout rows="*" columns="*">
<StackLayout visibility="{{ showLogin ? 'visible' : 'collapse'}}" row="0" column="0">
<!--Login form, as you have defined-->
</StackLayout>
<!--Indicator on whole page, colSpan and rowSpan force ActivityIndicator to takes whole page-->
<ActivityIndicator visibility="{{ !showLogin ? 'visible' : 'collapse'}}" busy="{{ !showLogin }}" rowSpan="1" colSpan="1" row="0" column="0" />
</GridLayout>
And inside javascript code
/*somehow add showLogin property to bindingContext*/
page.bindingContext.set("showLogin",false) //false for show ActivityIndicator
/*or*/
page.bindingContext.set("showLogin",true) //true for show form
But best would be to put to already defined Observable which you should have assigned to bindingContext
So based on showLogin property u will get visible either ActivityIndicator(on whole page) or form
Not sure if i forgot something but if something, write comment :)
The activity indicator on its own won’t prevent dual submissions of your forms. In addition to displaying an ActivityIndicator, you should also set the isEnabled flag on your Button UI components to false during the submission. For example:
<!-- template -->
<Button [isEnabled]="!isAuthenticating" (tap)="submit()"></Button>
// JavaScript/TypeScript
export class LoginComponent {
isAuthenticating = false;
submit() {
this.isAuthenticating = true;
doTheActualLogin()
.then(() => {
this.isAuthenticating = false;
});
}
}
You can find a complete implementation of a login that prevents dual submissions and uses an ActivityIndicator in the NativeScript Groceries sample. Take a look at how the isAuthenticating flag is used in this login folder for the specific implementation.

NativeScript binding breaks UI

I have setup a custom tab view defined as the following :
main.xml
<Page xmlns="http://schemas.nativescript.org/tns.xsd" loaded="loaded"
xmlns:t1="partial-views/explore"
xmlns:t2="partial-views/community">
<!--ACTION BAR-->
<ActionBar title="Haloose">...</ActionBar>
<StackLayout>
<!-- TABS -->
<StackLayout id="sl_main">
<t1:explore id="tab_explore" visibility="{{ currentActive == 'explore' ? 'visible' : 'collapsed' }}" />
<t2:community id="tab_community" visibility="{{ currentActive == 'community' ? 'visible' : 'collapsed' }}"/>
</StackLayout>
<-- FIXED MENU -->
<GridLayout id="menu">
<Image tap="changeVisibleTab"/>
<Image tap="changeVisibleTab" />
</GridLayout>
</StackLayout>
</Page>
Let's call this file main.xml . It's associated to a main.js where I've defined a binding context:
main.js
exports.loaded = function(args){
page = args.object;
//Set Up page view model
mainObservable = new Observable({
currentActive:"explore",
menuItemsArray:[
new MenuItem("explore"),
new MenuItem("community")
]
});
//Bind page to view model
page.bindingContext = mainObservable;
}
For each tab I have a folder containing a js , css and xml file.
A sample tab.xml file would look like this :
tab.xml
<StackLayout loaded="tabLoaded" > <looots of stuff /> </StackLayout>
Everything works as expected, however if I try to bind the stack layout to an object , all of the UI elements are hidden.
If I remove binding, I can see them again.
not working tab.js
var Observable = require("data/observable").Observable;
var profile;
exports.tabLoaded = function(args){
profile = args.object;
var profileBinding = {
username : "Aaron Ullal"
}
profile.bindingContext = profileBinding; //removing this line makes elements visible
}
What is causing this? Perhaps multi level binding is not supported?
When you use custom XML components, like your tabs, and add bindings to them (in your case the visibility binding, those bindings are basically applied to the root tag in your XML component. So when you change the binding context in your tab.js the visibility binding starts looking for a currentActive property in profileBinding. In order to achieve what you want you have to wrap your tab XML in another layout, like this:
<StackLayout>
<StackLayout loaded="tabLoaded" >
<!--looots of stuff -->
</StackLayout>
</StackLayout>
It should work as expected then.

Nativescript -Open SideDrawer on button click

I am using telerik ui for native script. I need a toggle button at top to open the side menu. but I am not able to call the Showdrawer() as per the docs.
What I need is on button click side menu should open. I tried calling RadSideDrawer.prototype.showDrawer(), but failed.
Is there any other side menu available for Nativescript?
main-page.xml
<Page xmlns="http://www.nativescript.org/tns.xsd" xmlns:drawer="nativescript-telerik-ui/sidedrawer" loaded="pageLoaded">
<Page.actionBar>
<ActionBar>
<android>
<NavigationButton text="Go Back" android.systemIcon="ic_menu_moreoverflow" tap="showSideDrawer" />
</android>
</ActionBar>
</Page.actionBar>
<drawer:RadSideDrawer>
<drawer:RadSideDrawer.mainContent>
<StackLayout>
<Label text="{{ mainContentText }}" textWrap="true" />
</StackLayout>
</drawer:RadSideDrawer.mainContent>
<drawer:RadSideDrawer.drawerContent>
<StackLayout cssClass="drawerContent" style="background-color:white;">
<StackLayout cssClass="headerContent">
<Label text="Header" />
</StackLayout>
<StackLayout cssClass="drawerMenuContent">
<Label text="Item 1" style="color:black;" />
<Label text="Item 2" style="color:black;" />
<Label text="Item 3" style="color:black;" />
<Label text="Item 4" style="color:black;" />
</StackLayout>
</StackLayout>
</drawer:RadSideDrawer.drawerContent>
</drawer:RadSideDrawer>
</Page>
getting-started-model.js
var observableModule = require("data/observable");
var GettingStartedViewModel = (function (_super) {
__extends(GettingStartedViewModel, _super);
function GettingStartedViewModel() {
_super.call(this);
this.set("mainContentText", "SideDrawer for NativeScript can be easily setup in the XML definition of your page by defining main- and drawer-content. The component"
+ " has a default transition and position and also exposes notifications related to changes in its state.");
}
return GettingStartedViewModel;
})(observableModule.Observable);
exports.GettingStartedViewModel = GettingStartedViewModel;
function showSideDrawer(args) {
console.log("Show SideDrawer tapped.");
// Show sidedrawer ...
_super.prototype.showDrawer.call(this);
}
exports.showSideDrawer = showSideDrawer;
main page.js
var viewModelModule = require("./getting-started-model");
function pageLoaded(args) {
console.log("Page loaded");
var page = args.object;
page.bindingContext = new viewModelModule.GettingStartedViewModel();
}
exports.pageLoaded = pageLoaded;
You can take a look at this SDK examples that show the main functionality of the RadSideDrawer. As mentioned by #R Pelzer all you need to do is get the instance of the RadSideDrawer for example by using its id:
import drawerModule = require("nativescript-telerik-ui-pro/sidedrawer");
import frameModule = require("ui/frame");
var sideDrawer: drawerModule.RadSideDrawer = <drawerModule.RadSideDrawer>(frameModule.topmost().getViewById("sideDrawer"));
and call its showDrawer() method:
sideDrawer.showDrawer();
Are you calling the showSideDrawer function from code you didn't post? Are you sure you linked the tap button?
<Button tap="showSideDrawer" text="ToggleDrawer"/>
Maybe you can try to give the sideDrawer an Id and use this code.
var drawer = frameModule.topmost().getViewById("sideDrawer");
drawer.showDrawer();
You are getting undefined because no id was assigned to the drawer so to fix your problem assign an id to the sideDrawer <drawer:RadSideDrawer id="sideDrawer"> then you can call
var frame = require('ui/frame');
var drawer = frame.topmost().getViewById("sideDrawer");
function showSideDrawer(){
drawer.showDrawer(); // i prefer using .toggleDrawerState();
};
In my case, I missed inserting , as a result, there was a missing component when toggleDrawer was being called hence the error "TypeError: Cannot read property 'toggleDrawerState' of undefined".
Try inserting all the body component of the xml file in this might solve the issue.
Happy coding :))

Find button or label inside Griview using Nativescript Grid view

I using GridView Nativescript to arrange the UI and I want to set css into specific button or label dynamically. How can I find inside label when outside button is trigger and I tried using getViewById method but always get empty result. Isn't got any method to find it ?
var gridview;
exports.onPageLoaded = function (args) {
page = args.object;
gridview = page.getViewById("gridview");
};
exports.onSelectedIndexChanged = function(args){
var totalMatch = 0;
var btn = args.object;
var index = btn.index;
var a = gridview.getViewById("25");
btn.backgroundColor = "red";
btn.color = "white";
};
<GridLayout columns="*,1,*,1,*" rows="auto" borderWidth="1" borderColor="#DBDBDB" borderRadius = "3" >
<Button text="selectALL" index="0" tap="onSelectedIndexChanged" backgroundColor= "red" id ="btnSelectAll" color="white" borderRadius="3" />
<Button text="UnselectAll" index="1" col="2" tap="onSelectedIndexChanged" backgroundColor= "white" id ="btnUnSelectAll" borderRadius = "3" />
<Border col="1" borderWidth="1" borderColor="#DBDBDB" />
<Border col="3" borderWidth="1" borderColor="#DBDBDB" />
</GridLayout>
<gv:GridView items="{{ items }}" verticalSpacing="3" horizontalSpacing="3" colWidth="100" rowHeight="50" padding="3" id="gridview" height="400">
<gv:GridView.itemTemplate>
<GridLayout backgroundColor="#ffffff" style="border-width:3px;border-color:#696969;border-radius:5">
<Button text="{{ Name }}" id="{{ Id }}" index="{{ Index }}" tap="onGridViewItemTap" backgroundColor= "white" color="red" style="background-size:100% 100%;background-repeat:no-repeat;background-image:url('~/images/drawable-hdpi-v4/spt_fiter_checked.png')" borderWidth="1" borderColor="#DBDBDB" borderRadius = "5"/>
</GridLayout>
</gv:GridView.itemTemplate>
</gv:GridView>
After my understanding, what you are trying to do is:
press the button in the GridLayout
trigger the onSelectedIndexChanged function
Access the button with id="25"
Modify the button
First, I would like to point out that it is not recommended to access views by ids, especially when you have a complex UI structure. I would suggest that you use bindings. I am not sure what exactly you would like to modify, so I will assume that you would like to change the background property of the button. In this case, you can bind an Observable object in the code to the background property in the XML. Then in the function onSelectedIndexChanged, you can modify the object in the code by setting a new color. Since it is observable, it will notify all of the listeners for the modification. And in our case - the property in the XML.
Here I am sending you a simple example:
main-page.xml
<Page xmlns="http://schemas.nativescript.org/tns.xsd" loaded="onPageLoaded">
<GridLayout rows="auto,auto" >
<Button text="Click to Change Color" row="0" tap="onSelectedIndexChanged"/>
<Button text="Button" row="1" backgroundColor="{{color}}"/>
</GridLayout>
</Page>
main-page.js
var observable = require("data/observable");
var json={color:'red'};
var changeCss = new observable.Observable(json);
var gridview;
exports.onPageLoaded = function (args) {
page = args.object;
page.bindingContext=changeCss;
};
exports.onSelectedIndexChanged = function(args){
changeCss.set("color","blue");
};
I hope this will give you some directions.

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