I'm facing this weird problem where I have a custom view (with custom drawing) overriding ToggleButton, and for some reason overriding the onDraw and draw methods do not prevent the parent class from drawing a part of it, which makes my view look like it's glitched.
This bug seems to be happening only with API level 25, on a physical device or on the emulator.
Using the following code for my custom toggle Button:
public class CustomToggleButton extends ToggleButton {
#TargetApi(Build.VERSION_CODES.LOLLIPOP)
public CustomToggleButton(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
}
public CustomToggleButton(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
public CustomToggleButton(Context context, AttributeSet attrs) {
super(context, attrs);
}
public CustomToggleButton(Context context) {
super(context);
}
#Override
protected void onDraw(Canvas canvas) {
//nope, not drawing anything
}
#Override
public void draw(Canvas canvas) {
//nope, not drawing anything
}
}
And the following simple XML layout:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="top|center_horizontal"
android:text="Bottom left: buggy custom ToggleButton.\nBottom right: regular ToggleButton." />
<test.com.togglebuttonbug.CustomToggleButton
android:layout_width="48dp"
android:layout_height="48dp"
android:layout_gravity="bottom|left"
android:textOff="B"
android:textOn="A" />
<ToggleButton
android:layout_width="48dp"
android:layout_height="48dp"
android:layout_gravity="bottom|right"
android:textOff="B"
android:textOn="A" />
</FrameLayout>
The result is the following:
If you look carefully at the screenshot, you can see that for the phone on the right, at the bottom left, instead of having nothing like the empty draw methods should do, you can see a piece of gray drawing.
Would anybody have an idea of what could be causing this? Is that a bug on Android N?
Related
How can i change those font attributes of a SwitchPreference?
I already tried to use app:layout attribute with the following layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="#android:id/title"
style="#android:style/TextAppearance.Widget.TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:fontFamily="MY-FONT"
android:text="Title" />
<TextView
android:id="#android:id/summary"
style="#android:style/TextAppearance.Widget.TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:fontFamily="MY-FONT"
android:text="Summary" />
</LinearLayout>
That doesn't work well, because the switch was missing and everything looks a bit messy.
What is an easy (and working) way to customize the fontfamily and textSize?
You need to create a Custom Switch Preference by extending its main class
public class CustomSwitchPreference extends SwitchPreference {
public CustomSwitchPreference(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
}
public CustomSwitchPreference(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
public CustomSwitchPreference(Context context, AttributeSet attrs) {
super(context, attrs);
}
public CustomSwitchPreference(Context context) {
super(context);
}
#Override
public void onBindViewHolder(PreferenceViewHolder holder) {
super.onBindViewHolder(holder);
TextView title1= (TextView) holder.findViewById(android.R.id.title);
title1.setTypeface(ResourcesCompat.getFont(getContext(),R.font.noto_sans_regular));
TextView title2= (TextView) holder.findViewById(android.R.id.summary);
title2.setTypeface(ResourcesCompat.getFont(getContext(),R.font.noto_sans_regular));
}
}
and use this is in your preferences xml
from
<SwitchPreference
.....
/>
to
<com.example.myapp.CustomSwitchPreference
....
/>
This Worked for me
To change the font family in android first you need to have the font in your app something like this
Your font goes in the font directory under res
Now to use it, your going in the right way
<Button
...
android:fontFamily="#font/nameOfFont"
... />
Let me now if it works for you
I need to create my own ImageView.
This is my class:
public class Brick extends ImageView implements Serializable{
public Brick(Context context) {
super(context);
}
public Brick(Context context, AttributeSet attrs) {
super(context, attrs);
}
public Brick(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
}
When I try to use my ImageView inside a xml layout file (as you can see below) I have a problem. I can see a black shape, but there is not the image (the drawable called d) inside it.
<com.myapp.Brick
android:id="#+id/myBrick"
app:srcCompat="#drawable/d"
android:background="#000000"
android:layout_width="300dp"
android:layout_height="300dp" />
What's my error?
You should call android:src="#drawable in your XML Section .
<com.myapp.Brick
android:id="#+id/myBrick"
app:srcCompat="#drawable/d"
android:background="#000000" // showing Black Shape Background
android:layout_width="300dp"
android:layout_height="300dp"
android:src="#drawable/add_image /> // Add android:src
You should add app:srcCompat or android:src in your XML Section
I am trying to extend a cardview to set the background image. I know that this can not be done with normal cardview. I have searched net and found plenty of solutions for setting a background color to the card view but none for image.
My code to do so:
public class CCView extends CardView {
public CCView (Context context) {
super(context);
init();
}
public CCView (Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public CCView (Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
setBackground(getResources().getDrawable(R.drawable.cc_background));
}
}
I get this exception when I populate the code from XML
android.graphics.drawable.BitmapDrawable cannot be cast to android.support.v7.widget.RoundRectDrawableWithShadow
Any solution?
As CardView extends FrameLayout you can layer layouts on top of it. To get around the problem you're having, I'd try adding a blank view "underneath" all the other elements in your view, and then set that view to inherit the state of its parent. Something like this:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_height="match_parent"
android:layout_width="match_parent"
card_view:cardBackgroundColor="#DDFFFFFF"
card_view:cardElevation="#dimen/card_elevation">
<View
android:layout_width="match_parent"
android:layout_height="match_parent"
android:duplicateParentState="true"
android:background="#drawable/card_background"/>
<LinearLayout
....
....
....
/LinearLayout>
</android.support.v7.widget.CardView>
custom view inside of a custom viewGroup not visible, how can I get it to show up?
or is there a better way to do this that would work?
no compile or runtime errors but the view does not show up in the viewGroup, it is supposed to fill the area with color like the other views but it is white and the color for the view is not showing up inside of the CustomLayout
xml code, the first 2 views show up with no problems but the 3rd view that is nested inside of the CustomLayout does not show up, just white color area, the view inside not visible
CustomViewOne is a separate class file, CustomViewTwo and CustomViewThree are both nested inside the MainActivity class as static inner classes, and CustomLayout is a separate file
<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:orientation="vertical"
tools:context=".MainActivity" >
<com.example.customviewexample.CustomViewOne
android:layout_width="100dp"
android:layout_height="50dp" />
<view
class="com.example.customviewexample.MainActivity$CustomViewTwo"
android:layout_width="100dp"
android:layout_height="50dp" />
<com.example.customviewexample.CustomLayout
android:layout_width="100dp"
android:layout_height="50dp">
<view
class="com.example.customviewexample.MainActivity$CustomViewThree"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</com.example.customviewexample.CustomLayout>
</LinearLayout>
here is the code for the CustomViewThree, vary simple like the other custom Views it just fills the area with color, it is nested inside of the MainActivity so you have to use MainActivity$CustomViewThree to access it.
public static class CustomViewThree extends View {
public CustomViewThree(Context context) {
super(context);
}
public CustomViewThree(Context context, AttributeSet attrs) {
super(context, attrs);
}
public CustomViewThree(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawColor(Color.GREEN);
}
}
and here is the code for the CustomLayout class
public class CustomLayout extends FrameLayout {
public CustomLayout(Context context) {
super(context);
init(context);
}
public CustomLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
public CustomLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context);
}
public void init(Context context) {
}
#Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
}
}
custom view inside of a custom viewGroup not visible, how can I get it
to show up?
Your parent CustomLayout which wraps the child has a empty onLayout() method which makes the child to not appear. This method is important in a ViewGroup because it's used by the widget to place its children in it. So, you need to provide an implementation for this method to place the children(by calling the layout() method on each of them with the proper positions). As CustomLayout extends FrameLayout you could just call the super method to use FrameLayout's implementation or even better remove the overridden method(is there a reason for implementing it?).
(Sorry for my poor question. I have update it now)
How can i make it in XML file? I tried to use following code, but not correct (I used "android:rotation="-90" to do rotation.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<FrameLayout
android:layout_width="141dp"
android:layout_height="200dp"
android:layout_weight="0.41"
android:orientation="vertical" >
<EditText
android:id="#+id/sidebar_title"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/shape_card_sidebar"
android:inputType="text"
android:rotation="-90"
android:text="I want to be like this" >
</EditText>
</FrameLayout>
You're going to run into several problems if you try to do it that way. The most obvious issue will be the incorrect measurement. Instead you should create a custom view. Something like this:
public class RotatedTextVew extends TextView {
public RotatedTextView(Context context) {
super(context);
}
public RotatedTextView(Context context, AttributeSet attrs) {
super(context, attrs)
}
public RotatedTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// Switch dimensions
super.onMeasure(heightMeasureSpec, widthMeasureSpec);
}
#Override
protected void onDraw(Canvas canvas) {
canvas.save();
canvas.rotate(90);
super.onDraw(canvas);
canvas.restore();
}
}
I haven't actually tested this, but this is how I'd start.
Replace your FrameLayout with <Relative> or <LinearLayout>. Also set android:gravity="center" property of parent layout.