自定义textview实现竖直滚动跑马灯效果

xml布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="myandroidstituds.test3.MainActivity">

<LinearLayout
android:layout_centerInParent="true"
android:layout_width="180dp"
android:layout_height="50dp">
<TextView
android:padding="10dp"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#55000000"
/>
</LinearLayout>
<myandroidstituds.test3.MarqueeLayout
android:id="@+id/mar"
android:layout_centerInParent="true"
android:layout_width="180dp"
android:layout_height="50dp">
<TextView
android:id="@+id/tv1"
android:textSize="20sp"
android:gravity="center"
android:background="@android:color/transparent"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textColor="#000000"
android:visibility="gone"
android:text="两个黄鹂鸣翠柳"
/>
<TextView
android:id="@+id/tv2"
android:textSize="20sp"
android:background="@android:color/transparent"
android:gravity="center"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textColor="#000000"
android:visibility="gone"
android:text="一行白鹭上青天"
/>
</myandroidstituds.test3.MarqueeLayout>
</RelativeLayout>

自定义MarqueeLayout

public class MarqueeLayout extends FrameLayout implements ViewTreeObserver.OnGlobalLayoutListener{
private View view1;
private View view2;
public int interval = 2000;
public MarqueeLayout(Context context) {
this(context,null);
}
public MarqueeLayout(Context context, AttributeSet attrs) {
this(context, attrs,0);
}
public MarqueeLayout(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
getViewTreeObserver().addOnGlobalLayoutListener(this);
}
@Override
protected void onFinishInflate() {
super.onFinishInflate();
if(getChildCount()!=2){
throw  new IllegalArgumentException("MarqueeLayout should have 2 child!");
}
view1 = getChildAt(0);
view2 = getChildAt(1);
}
@Override
public void onGlobalLayout() {
getViewTreeObserver().removeGlobalOnLayoutListener(this);

view2.setTranslationY(view2.getHeight());
}

private Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
startAnim();
}
};
boolean isAniming = false;
/**
* 开始滚动
*/
public void start(){
getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
getViewTreeObserver().removeGlobalOnLayoutListener(this);
startAnim();
}
});
}
public void startAnim(){
if(isAniming)return;

isAniming = true;
int targetY1 = view1.getTranslationY()==0?-view1.getHeight():0;
int targetY2 = view2.getTranslationY()==0?-view2.getHeight():0;

ViewCompat.animate(view1)
.translationY(targetY1)
.setListener(new ViewPropertyAnimatorListenerAdapter(){
@Override
public void onAnimationEnd(View view) {
super.onAnimationEnd(view);
//移动到下方
resetView(view);
}
})
.setDuration(400).start();
ViewCompat.animate(view2)
.translationY(targetY2)
.setListener(new ViewPropertyAnimatorListenerAdapter(){
@Override
public void onAnimationEnd(View view) {
super.onAnimationEnd(view);
//移动到下方
resetView(view);
isAniming = false;
handler.sendEmptyMessageDelayed(0,interval);
}
})
.setDuration(400)
.start();
}
private void resetView(View view) {
if(view.getTranslationY()==-view.getHeight()){
view.setTranslationY(view.getHeight()*2);
}
}
public void stop(){
handler.removeCallbacksAndMessages(null);
}
}

在Activity中的使用

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

MarqueeLayout marqueeLayout = (MarqueeLayout) findViewById(R.id.mar);
TextView tv1 = (TextView) findViewById(R.id.tv1);
TextView tv2 = (TextView) findViewById(R.id.tv2);
marqueeLayout.start();
tv1.setVisibility(tv1.getTranslationY() == 0 ? View.VISIBLE : View.GONE);
tv2.setVisibility(tv2.getTranslationY() == 0 ? View.VISIBLE : View.GONE);

}
}