I have custom view which extends imageview (with glow touch). I want to add elements like buttons, textviews, to make glow touch when they are touched. I read that custom view cannot have children because only layouts can have them.
Is there any workaround to solve this stuff?
Code:
public class CustomView extends ImageView{
public CustomView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public CustomView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public CustomView(Context context) {
super(context);
.........
}
With regards
You are correct about the fact that only layouts (ViewGroups) can contain Views, and Views itself can not.
Instead of making a custom View, you can make a custom ViewGroup. In there you can add the Views you need, like the ImageViews and the others you mention (Buttons, EditText, etc).
Related
My layout has a lot of elements and I want to divide them using "divider":
<View
android:id="#+id/divider"
android:layout_width="match_parent"
android:layout_height="2dp"
android:background="#android:color/black"/>
But I don't want to add the same divider 10 times in layout. Can I do something to help me to add divider only one time? With button I have the same question. I have 3 button in different places in my layout, but this button doing the same. How can i bind one action for three button and add only one time in layout?
If you have a lot of Items that use the same layout, ie. they look a lot like each other, ListView with an ArrayAdapter is very, very useful.
You can done this type of job by creating custom button. Custom button extends the Button class. Something like this e.g:
public class MyButton extends Button {
public MyButton(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(attrs);
}
public MyButton(Context context, AttributeSet attrs) {
super(context, attrs);
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
inflater.inflate(R.layout.your_custom_button_layout, this, true);
}
public MyButton(Context context) {
super(context);
}
}
I'm having trouble understanding why my extended layout isn't working. I made a class which goes
public class MyLayout extends RelativeLayout {
public MyLayout(Context context) {
super(context);
}
}
I wrote the XML as
<package.MyLayout
. . .
</package.MyLayout>
The method where I get the error is in the activity where I have called setContentView(R.layout.layout_relative).
I don't understand what I'm doing wrong because surely you inflate in the activity from the XML layout which is building on the custom class where I can make my overrides?
you need the other constructor, the one that takes two parameters:
public MyLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
which is used when the layout is inflated from the layout
You have specified the wrong constructors!
Android xml inflation uses
public RelativeLayout (Context context, AttributeSet attrs, int
defStyleAttr)
public RelativeLayout (Context context, AttributeSet
attrs, int defStyleAttr, int defStyleRes) since api 21
i want use all the component in android which having the same font type face, for that i am creating a individual custom class for each component like CustomTextView, CustomEditText, etc,..
So instead of creating a individual class for each component can i create a view CustomView class that will automatically apply style for all the components in android
Just declare your own TextView and use it in your XML, it should appear in the custom Views
public class MyTextView extends TextView {
public MyTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
setType(context);
}
public MyTextView(Context context, AttributeSet attrs) {
super(context, attrs);
setType(context);
}
public MyTextView(Context context) {
super(context);
setType(context);
}
private void setType(Context context){
this.setTypeface(Typeface.createFromAsset(context.getAssets(), "chalk_board.ttf"));
}
Oh dam u want it globally for all views, so this is the wrong approach.... Sorry for that
You have at least 2 ways:
create your own TextView class and set fontFace in constructor
you can use custom LayoutInflater. And every time view gets inflated check that it is textView (or other view not extending textView but having font settings) and set correct fontFace settings.
does anybody know, how to get a referenced xml layout, programmatically (in code) for my custom widget. I have already created a custom declare-styleable, with my desired attributes and I know how to get ohter xml attribute values, like string or integers.
What I want to do is something like this:
<MyCustomView
xmlns:my="http://schemas.android.com/apk/res-auto"
id="#+id/view"
my:headerLayout="#layout/my_fancy_layout"
/>
So I want to retrieve my_fancy_layout programmatically and inflate that layout in the code of MyCustomView.
Any idea how to do that?
Edit: I guess I can retreive the resource id with
int resId = attrs.getAttributeResourceValue(androidns, "headerLayout", 0);
But whats the correct namespace if I MyCustomView is a library project and if I would like to use
xmlns:my="http://schemas.android.com/apk/res-auto"
Ok, i found the solution by myself:
you have to retrieve a TypedArray from yout AttributeSet.
than you can access your desired resource id with something like this:
TypedArray attrs = ... ;
int headerRes = attrs.getResourceId(R.styleable.MyCustomWidget_headerLayout, -1);
than you can inflate like usually:
LayoutInflater.from(context).inflate(headerRes, this);
You can indeed inflate your layout in the constructor of your custom view:
public class MyCustomView extends /* LinearLayout, RelativeLayout, etc. */ {
public MyCustomView(Context context, AttributeSet attrs) {
super(context, attrs);
initView(context, attrs);
}
public MyCustomView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initView(context, attrs);
}
protected void initView(Context context, attrs) {
LayoutInflater.from(context).inflate(attrs.getAttributeResourceValue("http://schemas.android.com/apk/res-auto", "headerLayout", 0), this, true);
}
}
I want to create a custom view TestView class for which I can create object via new TestView().
A new view class however needs a AttributeSet object. From where do I get that AttributeSet and what does it have to include?
It's not mandatory, and most times you don't even have to worry about it as long as you provide constructors from View that pass them along to super().
public CustomView(Context context) // No Attributes in this one.
{
super(context);
// Your code here
}
public CustomView(Context context, AttributeSet attrs)
{
super(context, attrs);
// Your code here
}
public CustomView(Context context, AttributeSet attrs, int default_style)
{
super(context, attrs, default_style);
// Your code here
}
View takes care of doing the heavy lifting for dealing with all of the android:* attributes that you'd usually pass in when adding the view to a layout. Your constructors could make use of those attributes or your own if you've defined them:
<com.blrfl.CustomView
android:id="#+id/customid"
android:layout_weight="1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_gravity="center"
blrfl:foo="bar"
blrfl:quux="bletch"
/>
Either of 3 constructor provided by view class can be implemented.. so providing constructor with attributeset is not mandatory.