Android TV是一种基于Android操作系统的智能电视平台,具有许多独特的功能。下面是一个实现焦点放大功能的代码示例:
在XML布局文件中,为要放大焦点的视图添加属性android:focusable="true"
和android:clickable="true"
。例如:
在Java代码中,为视图设置焦点监听器,并在焦点变化时调整视图的缩放。例如:
import android.animation.AnimatorSet;
import android.animation.ObjectAnimator;
import android.os.Bundle;
import android.view.View;
import android.view.animation.DecelerateInterpolator;
import android.widget.Button;
public class MainActivity extends Activity {
private Button myButton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myButton = findViewById(R.id.myButton);
myButton.setOnFocusChangeListener(new View.OnFocusChangeListener() {
@Override
public void onFocusChange(View v, boolean hasFocus) {
if (hasFocus) {
animateView(v, 1.2f);
} else {
animateView(v, 1f);
}
}
});
}
private void animateView(View view, float scale) {
ObjectAnimator scaleX = ObjectAnimator.ofFloat(view, "scaleX", scale);
ObjectAnimator scaleY = ObjectAnimator.ofFloat(view, "scaleY", scale);
AnimatorSet animatorSet = new AnimatorSet();
animatorSet.playTogether(scaleX, scaleY);
animatorSet.setDuration(200);
animatorSet.setInterpolator(new DecelerateInterpolator());
animatorSet.start();
}
}
在上面的代码中,我们在onCreate
方法中找到了我们的按钮视图,并为其设置了焦点监听器。在焦点变化时,我们调用了animateView
方法来实现缩放效果。animateView
方法使用ObjectAnimator
来实现逐渐缩放的动画效果。