Android自定义textview实现竖直滚动跑马灯效果

<?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>

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);  }}

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);  }}