如何在Android上的现有XML布局中包含自定义视图？

Question

I have followed this tutorial ( http://stuffthathappens.com/blog/2008/11/13/android-animation-101/ ) and have a beautiful rotating text being drawn onto a canvas. Everything works perfectly when my main activity uses

setContentView(new SplashScreenAnimation(this));

Here is SplashScreenAnimation:

public class SplashScreenAnimation extends View {
    private static final String QUOTE = "Nobody uses Java anymore. It's this big heavyweight ball and chain.";

    private Animation anim;

    public SplashScreenAnimation(Context context) {
        super(context);
    }

    private void createAnim(Canvas canvas) {
        anim = new RotateAnimation(0, 360, canvas.getWidth() / 2, canvas
                .getHeight() / 2);
        anim.setRepeatMode(Animation.REVERSE);
        anim.setRepeatCount(Animation.INFINITE);
        anim.setDuration(10000L);
        anim.setInterpolator(new AccelerateDecelerateInterpolator());

        startAnimation(anim);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        // Creates the animation the first time
        if (anim == null) {
            createAnim(canvas);
        }

        Path circle = new Path();

        int centerX = canvas.getWidth() / 2;
        int centerY = canvas.getHeight() / 2;
        int r = Math.min(centerX, centerY);

        circle.addCircle(centerX, centerY, r, Direction.CW);
        Paint paint = new Paint();
        paint.setColor(Color.BLUE);
        paint.setTextSize(30);
        paint.setAntiAlias(true);

        canvas.drawTextOnPath(QUOTE, circle, 0, 30, paint);
    }
}

However I want to combine this animated text and have two buttons underneath it so I have a RelativeLayout:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout android:id="@+id/RelativeLayout1"
 xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="vertical" android:layout_width="fill_parent"
 android:layout_height="fill_parent" android:background="@drawable/splash_screen">
 <LinearLayout android:orientation="vertical"
  android:layout_height="wrap_content" android:layout_width="fill_parent"
  android:layout_alignParentBottom="true" android:id="@+id/bottomLinearLayout">
  <Button android:layout_gravity="center_horizontal" android:id="@+id/playButton"
   android:text="Button" android:layout_height="wrap_content"
   android:layout_width="wrap_content"></Button>
  <Button android:layout_height="wrap_content"
   android:layout_width="wrap_content" android:id="@+id/optionsButton"
   android:text="Button" android:layout_gravity="center_horizontal"
   android:layout_marginBottom="30sp"></Button>
 </LinearLayout>


 <LinearLayout android:id="@+id/topLinearLayout"
  android:orientation="vertical" android:layout_height="wrap_content"
  android:layout_alignParentTop="true" android:layout_width="fill_parent">
 </LinearLayout>

</RelativeLayout>

How can I add this custom view to the LinearLayout above? (topLinearLayout - it's the last one)

I've tried a lot of different things, and I keep ending up with force closes.

This sort of approach has been mainly what I've tried. I've tried inflating it, etc.

LinearLayout item = (LinearLayout)findViewById(R.id.topLinearLayout);
SplashScreenAnimation child = new SplashScreenAnimation(this);
item.addView(child);

I added entire SplashScreenAnimation class code:

((LinearLayout) findViewById(R.id.topLinearLayout)).addView(new SplashScreenAnimation(this))

It works!!

Why won't the other methods of adding it manually work? Has it something to do with the fact the animation needs to start via onDraw ?

Answer 1

You should be able to include it just like any other view in your layout.

Try the following and then set your content view to the entire XML layout:

<LinearLayout android:id="@+id/topLinearLayout"
  android:orientation="vertical" android:layout_height="wrap_content"
  android:layout_alignParentTop="true" android:layout_width="fill_parent">
      <com.YOURPACKAGENAME.SplashScreenAnimation
           android:id="@+id/animation"
           android:layout_height="wrap_content"
           android:layout_width="wrap_content"/>
 </LinearLayout>

Answer 2

It's pretty easy, and you just need to include the full package name of the class extending the View class:

<LinearLayout
    android:id="@+id/topLinearLayout"
    android:orientation="vertical"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_width="fill_parent">

       <mypackage.SplashScreenAnimation
           android:layout_height="wrap_content"
           android:layout_width="fill_parent"/>

</LinearLayout>

Answer 3

尝试以下行添加视图：

((LinearLayout) findViewById(R.id.topLinearLayout)).addView(new SplashScreenAnimation(this))