I'm having trouble creating a custom view.
If my understanding is correct, i wish for a compound view where ui elements like Switch can be incorporated within a custom view. An example of intention of this will be a modal view that displays a series of switches with a save & back button with relative actions, in context to an in-app form purpose.
In other examples/questions people have mentioned this.addView(View childView) however when i try to use this function i get an unresolved symbol error from android studio. When executed, the app displays blank.
public class NewView extends View {
private Switch switchOne;
private Switch switchTwo;
public NewView(Context context){
super(context);
init(null, 0);
}
public NewView(Context context, AttributeSet attrs){
super(context);
init(attrs, 0);
}
public NewView(Context context, AttributeSet attrs, int defStyle){
super(context);
init(attrs, defStyle);
}
private void init(AttributeSet attrs, int defStyle) {
//LayoutInflater.from(getContext()).inflate(R.layout.customview, (ViewGroup) this.getParent(), true); //First attempted this approach
((Activity) getContext()).getLayoutInflater().inflate(R.layout.customview, (ViewGroup) this.getParent()); //then attempted this approach
this.switchOne = (Switch) findViewById(R.id.firstSwitch);
this.switchTwo = (Switch) findViewById(R.id.secondSwitch);
}
#Override
public void onDraw(Canvas canvas){
super.onDraw(canvas);
}
}
customview.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/mainView">
<Switch
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/firstSwitch"/>
<Switch
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/secondSwitch"/>
</LinearLayout>
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:orientation="vertical"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context=".MainActivity">
<com.example.simonaddicott.customviewone.NewView
android:layout_height="match_parent"
android:layout_width="match_parent"
android:id="#+id/myNewView"
/>
</LinearLayout>
Extend from ViewGroup, override onLayout and provide an implementation. Alternatively, since you seem to just want the switches laid out vertically, just extend from LinearLayout to reuse its layout rules and set the orientation for your NewView in the activity_main.xml, or in code if you want to override the xml setting and enforce the vertical layout.
Replace the root LinearLayout in customview.xml with a merge.
When inflating, use this and not this.getParent() as the second parameter
Related
I use this kind of ViewGroup:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ImageView
android:id="#+id/icon"
android:layout_width="16dp"
android:layout_height="16dp"
android:src="#drawable/icon1"/>
<TextView
android:id="#+id/title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/text1"/>
<TextView
android:id="#+id/data"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
I must use 2 such layouts In my fragment, but with different icon and title. Is there some way to implement it without copy/paste and RecyclerView?
There are several ways to deal with it.
1. Use the include tag.
1.1. Move LinearLayout to a separate file.
1.2 Add layout using the include tag two times with different ids:
<LinearLayout ...>
<include layout="#layout/your_layout" android:id="#+id/first" />
<include layout="#layout/your_layout" android:id="#+id/second" />
</LinearLayout>
1.3 Set content programmatically:
View first = findViewById(R.id.first);
first.findViewById(R.id.date).setText("05/05/2020");
View second = findViewById(R.id.second);
second.findViewById(R.id.date).setText("04/04/2020");
2. Implement a custom view.
There are two ways also. The first is to inflate layout inside FrameLayout. The second is to extend LinearLayout and add content programmatically. I'll show you the first one.
public class YourCustomView extends FrameLayout {
public MyView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
inflate(context, R.layout.your_custom_view_layout, this);
}
public MyView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public MyView(Context context) {
this(context, null);
}
public void setContent(int iconRes, int titleRes, String data) {
findViewById(R.id.icon).setDrawableRes(iconRes);
findViewById(R.id.title).setDrawableRes(titleRes);
findViewById(R.id.data).setText(data);
}
}
3. Just copy-paste it :)
As I see icon and title are static and only data content changes, so it is not worth it to reuse such a simple layout, IMO.
I've got a custom view for my app named AvatarView:
<?xml version="1.0" encoding="utf-8"?>
<com.ulouder.views.AdvancedRelativeLayout android:layout_width="wrap_content"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_gravity="center_horizontal"
android:layout_margin="0dp"
android:padding="0dp"
xmlns:android="http://schemas.android.com/apk/res/android">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="CP"
android:id="#+id/initialsView"
android:layout_alignTop="#+id/avatarView"
android:layout_alignLeft="#+id/avatarView"
android:layout_alignBottom="#+id/avatarView"
android:layout_alignRight="#+id/avatarView"
android:background="#drawable/avatar_background"
android:textColor="#color/white"
android:gravity="center"
android:textStyle="bold"
android:textSize="8sp" />
<com.makeramen.roundedimageview.RoundedImageView
app:riv_corner_radius="20dp"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/avatarView"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="4dp"
android:layout_marginLeft="4dp"
android:layout_marginBottom="4dp"
app:riv_border_color="#color/lightGray"
app:riv_border_width="0.2dp" />
</com.uLouder.views.AdvancedRelativeLayout>
AdvancedRelativeLayout is just a superclass of RelativeLayout with a small fix, nothing special there. Then, I've created a view that uses my custom view:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<com.ulouder.views.AvatarView
android:layout_width="50dp"
android:layout_height="50dp"/>
</LinearLayout>
Nothing fancy either. But in the designer view of the second layout XML, I'm getting this:
The editor displays my view hierarchy like it has a nested instance of itself, while clearly there isn't. If I delete either one, they both get deleted. If I declare attributes on one of them, other also gets it. They are clearly the same instance. The only exception is setting an ID. Then the problem disappears, and only single instance is displayed as expected.
I've rebuilt the project, restarted Android Studio, but it's still the same. What am I doing wrong?
UPDATE: Nope, now, after editing id, the problem still continues again.
UPDATE 2: It's not just a layout so I can't use <include> tag. It's a custom view which has custom logic inside.
UPDATE 3: Here is my custom view's (relevant) code:
public class AvatarView extends FrameLayout {
public AvatarView(Context context) {
super(context);
init();
}
TextView initialsView;
RoundedImageView imageView;
public AvatarView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
void init(){
inflate(getContext(), R.layout.view_avatar, this);
initialsView = (TextView) findViewById(R.id.innerInitialsView);
imageView = (RoundedImageView) findViewById(R.id.innerImageView);
}
#SuppressWarnings("SuspiciousNameCombination")
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, widthMeasureSpec); //always square
imageView.setCornerRadius(widthMeasureSpec / 2f);
initialsView.setTextSize(TypedValue.COMPLEX_UNIT_DIP, widthMeasureSpec * 30f);
}
}
UPDATE 4: It appears that this happens wherever I put my custom AvatarView class, not just at one place.
I did not find any reason to inflate the same view inside your class constructor method after checking the custom views documentation. Try to remove the inflate inside your init method.
...
public AvatarView(Context context) {
super(context);
init();
}
...
public AvatarView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
void init(){
// inflate(getContext(), R.layout.view_avatar, this);
initialsView = (TextView) findViewById(R.id.innerInitialsView);
imageView = (RoundedImageView) findViewById(R.id.innerImageView);
}
...
I have a hierarchy of custom views that looks like this:
Activity(RelativeLayout) -> ParentLayout(FrameLayout) -> ChildLayout(LinearLayout)
The activity and parent layout are added and displayed just fine, but the child is not. I have looked at the hierarchy viewer in the device monitor to confirm it is not being added to the view hierarchy.
Really all I'm trying to do here is create a view hierarchy so I can play around with handling touch events at various places in the view.
Here is everything:
main_activity.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity">
<net.openeye.touchevents.ParentLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#558833" />
</RelativeLayout>
parent_layout.xml:
<?xml version="1.0" encoding="utf-8"?>
<net.openeye.touchevents.ParentLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<net.openeye.touchevents.ChildLayout
android:id="#+id/child_view"
android:layout_width="300dp"
android:layout_height="300dp" />
</net.openeye.touchevents.ParentLayout>
ParentLayout.java:
public class ParentLayout extends FrameLayout implements View.OnTouchListener {
public ParentLayout(Context context) {
super(context);
}
public ParentLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public ParentLayout(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
}
child_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<net.openeye.touchevents.ChildLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="300dp"
android:layout_height="300dp"
android:background="#0066dd"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="Hi"/>
</net.openeye.touchevents.ChildLayout>
ChildLayout.java:
public class ChildLayout extends LinearLayout {
public ChildLayout(Context context) {
super(context);
}
public ChildLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public ChildLayout(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
}
What am I missing? I have another project that is basically set up the same way, except the child views are dynamically inflated and added, instead of being directly added in the xml layout files. This seems like it should work and I don't understand why it doesn't.
So it looks like when you have a custom view class, you don't want to have the view of the layout file be the same type as the custom class. i.e., if I have ParentLayout.java, I don't want parent_layout.xml's root to be <net.openeye.TouchEvents.ParentLayout>. It seems that when you want both a custom layout file and custom view class, you need to have the view class inflate the layout. If the layout has an element (the root, on this case) that is the same as the class, it will cause infinite recursion as the view inflates the layout, which instantiates the class, which inflates the layout... and so on.
I got this to work finally by making the following changes:
parent_layout.xml:
Change the root element from net.openeye.TouchEvents.ParentLayout to the class it extends, FrameLayout. It now looks like this:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- ... -->
</FrameLayout>
child_layout.xml:
Change the root element from net.openeye.TouchEvents.ChildLayout to the class it extends, LinearLayout. It now looks like this:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="300dp"
android:layout_height="300dp"
android:orientation="vertical">
<!-- ... -->
</LinearLayout>
ParentLayout.java: Inflate it's layout during instantiation. It now looks like this:
public ParentLayout(Context context) {
super(context);
init(context);
}
public ParentLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
public ParentLayout(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(context);
}
private void init(Context context) {
inflate(context, R.layout.parent_layout, this);
}
ChildLayout.java: Same thing as ParentLayout.java, but inflate child_layout.
After getting this working and thinking about why this is happening, it makes sense that this is how it works.
How do I add a hint on the top of a listView like "Pull down to refresh" which is contained in a swipeRefreshLayout from android.support.v4.
The pull down to refresh works but I want to add a text whenever the user pulls the listview slightly down.
EDIT 10/21/2014
If you update the support-v4 to the latest version (at least 21.0.0) you can use the built-in loading indicator!
I just came up with a simple, yet effective, solution.
The idea is to add a custom ViewGroup that grows its height when the SwipeRefreshLayout child gets pulled down. In this ViewGroup you will put everything you need for your hint (TextViews, ImageViews, ...).
I chose to extend a RelativeLayout because it makes easier to position your "hint" elements.
1) Create a custom widget as follows:
public class SwipeRefreshHintLayout extends RelativeLayout {
public SwipeRefreshHintLayout(Context context) {
super(context);
}
public SwipeRefreshHintLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public SwipeRefreshHintLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public void setSwipeLayoutTarget(final SwipeRefreshLayout swipeRefreshLayout) {
final View swipeTarget = swipeRefreshLayout.getChildAt(0);
if (swipeTarget == null) {
return;
}
swipeTarget.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
private Rect oldBounds = new Rect(), newBounds = new Rect();
#Override
public boolean onPreDraw() {
newBounds.set(swipeTarget.getLeft(), swipeRefreshLayout.getTop(), swipeTarget.getRight(), swipeTarget.getTop());
if (!oldBounds.equals(newBounds)){
getLayoutParams().height = newBounds.height();
requestLayout();
oldBounds.set(newBounds);
}
return true;
}
});
}
}
2) In your Fragment or Activity layout use this custom widget.
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<com.example.widget.SwipeRefreshHintLayout
android:id="#+id/swipe_hint"
android:layout_width="match_parent"
android:layout_height="0dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:text="#string/label_swipe_to_refresh"/>
<!-- Any other view positioned using RelativeLayout rules -->
</com.example.widget.SwipeRefreshHintLayout>
<android.support.v4.widget.SwipeRefreshLayout
android:id="#+id/swipe_container"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</android.support.v4.widget.SwipeRefreshLayout>
</RelativeLayout>
3) Then, in your Activity onCreate() or in your Fragment onCreateView(), put those lines:
mSwipeRefreshLayout = (SwipeRefreshLayout) rootView.findViewById(R.id.swipe_container);
mSwipeRefreshHintLayout = (SwipeRefreshHintLayout) rootView.findViewById(R.id.swipe_hint);
mSwipeRefreshHintLayout.setSwipeLayoutTarget(mSwipeRefreshLayout);
Done!
I am learning to create a compound control in android.
For starters i tried an edit text with an attached button to clear it.
The problem is even though i can see the compound control in the graphical view of the
main.xml, there is an error message : "Custom view ClearableEditText is not using the 2- or 3-argument View constructors; XML attributes will not work"
This is not visible in project explorer under errors only in the xml graphical view
i am able to compile and run but get a force close.
XML : COMPOUND CONTROL clearable_edit_text.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<EditText android:id="#+id/editText"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<Button android:id="#+id/clearButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="CLEAR"
/>
</LinearLayout>
CLASS
public class ClearableEditText extends LinearLayout
{
EditText et;
Button btn;
public ClearableEditText(Context context)
{
super(context);
LayoutInflater li=(LayoutInflater)getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
li.inflate(R.layout.clearable_edit_text,this,true);
et=(EditText)findViewById(R.id.editText);
btn=(Button)findViewById(R.id.clearButton);
hookupButton();
}
private void hookupButton()
{
btn.setOnClickListener(new Button.OnClickListener()
{
public void onClick(View v)
{
et.setText("");
}
});
}
}
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<com.commsware.android.merge.ClearableEditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<com.commsware.android.merge.ClearableEditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
Your class extends LinearLayout but you never add any views to it. You need to call addView(...) and pass your inflated view as the parameter.
Also, to define your view in XML you need to override the 2 and 3 argument constructors for a LinearLayout. Add this to your code:
public ClearableEditText(Context context, AttributeSet attrs) {
super( context, attrs );
}
public ClearableEditText(Context context, AttributeSet attrs, int defStyle) {
super( context, attrs, defStyle );
}
To get all 3 constructors to use the same initialization code, move your code from the single argument constructor to the 3 argument constructor, then in the other 2 constructors call this(context, null, 0) and this(context, attrs, 0) respectively.