Android 文字上下滚动显示

一、前言：

我们APP的通知要在类似输入框中，文字上下滚动显示，效果如下：

图片.png
gitee地址：https://gitee.com/lyyon/MarqueeTextViewDemo

二、代码：

1、调用：

  //组装数据
        var announcementList = mutableListOf<Announce>()
        announcementList.add(Announce("标题1"))
        announcementList.add(Announce("标题2"))
        announcementList.add(Announce("标题3"))
        //调用方法
        binding.tvContext.setTextArraysAndClickListener(announcementList,
            MarqueeTextViewClickListener { view, position ->
                val title = announcementList.getOrNull(position)?.title
                Log.d("lyy","----title:${title}")
                //执行对应的跳转逻辑
            })

2、XML

  <androidx.constraintlayout.widget.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="40dp"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/btn_click"
            android:layout_marginTop="35dp"
            android:background="@drawable/btn_shap_13"
            android:layout_marginHorizontal="20dp"
            >

            <ImageView
                android:id="@+id/iv_horn"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:src="@mipmap/bookshelf_horn"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:layout_constraintBottom_toBottomOf="parent"
                android:layout_marginStart="9dp"
                />
            <com.youjiakeji.helloaa.tools.MarqueeTextView
                android:id="@+id/tv_context"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_marginStart="7dp"
                tools:text="新用户更享好礼活动 "
                tools:ignore="MissingConstraints"
                app:layout_constraintStart_toEndOf="@+id/iv_horn"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:layout_constraintBottom_toBottomOf="parent"
                />

        </androidx.constraintlayout.widget.ConstraintLayout>

3、Announce对象

public class Announce {

    /**
     * title : 每日更新好书，等你来读
     * content : 每日更新好书，等你来读。
     */
    private String title;
    private String content;

    public Announce(String title) {
        this.title = title;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }

    @Override
    public String toString() {
        return "Announce{" +
                "title='" + title + '\'' +
                ", content='" + content + '\'' +
                '}';
    }
}

4、MarqueeTextView

package com.youjiakeji.helloaa.tools;

import android.content.Context;
import android.graphics.Color;
import android.os.Handler;
import android.os.Looper;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.animation.AnimationUtils;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.ViewFlipper;

import com.youjiakeji.helloaa.R;

import java.util.List;

/**
 * 文字上下滚动
 */
public class MarqueeTextView extends LinearLayout {

    private Context mContext;
    private ViewFlipper viewFlipper;
    private View marqueeTextView;
    private List<Announce> textArrays;
    private MarqueeTextViewClickListener marqueeTextViewClickListener;
    int mWidth;
    int mHeight;
    private Handler mHandler;

    public MarqueeTextView(Context context) {
        super(context);
        mContext = context;
        initBasicView();
    }

    public MarqueeTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mContext = context;
        initBasicView();
    }

    public void setTextArraysAndClickListener(List<Announce> textArrays, MarqueeTextViewClickListener marqueeTextViewClickListener) {
        this.textArrays = textArrays;
        this.marqueeTextViewClickListener = marqueeTextViewClickListener;
        initMarqueeTextView(textArrays, marqueeTextViewClickListener);
    }

    public void initBasicView() {
        mHandler = new Handler(Looper.getMainLooper());
        marqueeTextView = LayoutInflater.from(mContext).inflate(R.layout.marquee_textview_layout, null);
        LayoutParams layoutParams = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
        addView(marqueeTextView, layoutParams);
        viewFlipper = marqueeTextView.findViewById(R.id.viewFlipper);
        viewFlipper.setInAnimation(AnimationUtils.loadAnimation(mContext, R.anim.slide_in_bottom));
        viewFlipper.setOutAnimation(AnimationUtils.loadAnimation(mContext, R.anim.slide_out_top));
        viewFlipper.startFlipping();
        viewFlipper.setFlipInterval(5000);
    }

    public void initMarqueeTextView(List<Announce> textArrays, final MarqueeTextViewClickListener marqueeTextViewClickListener) {
        if (textArrays.size() == 0) {
            return;
        }
        viewFlipper.removeAllViews();
        checkInit();
    }

    /**
     * 检测控件是否初始化完毕
     */
    public void checkInit() {

        Runnable checkRunnable = new Runnable() {
            @Override
            public void run() {
                if (mHeight > 0) {
                    int i = 0;
                    while (i < textArrays.size()) {
                        final int j = i;
                        TextView textView = new TextView(mContext);
                        textView.setLines(1);
                        textView.setTextColor(Color.WHITE);
                        textView.setText(textArrays.get(i).getTitle());
                        textView.setTextSize(15);
                        textView.setGravity(Gravity.CENTER_VERTICAL);
                        textView.setOnClickListener(new OnClickListener() {
                            @Override
                            public void onClick(View v) {
                                marqueeTextViewClickListener.onClick(v, j);
                            }
                        });
                        ViewFlipper.LayoutParams lp = new ViewFlipper.LayoutParams(ViewFlipper.LayoutParams.MATCH_PARENT, mHeight);
                        viewFlipper.addView(textView, lp);
                        i++;
                    }
                    mHandler.removeCallbacks(this);
                } else {
                    mHandler.postDelayed(this, 5);
                }
            }
        };
        // 开始检测
        mHandler.post(checkRunnable);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        mWidth = MeasureSpec.getSize(widthMeasureSpec);
        mHeight = MeasureSpec.getSize(heightMeasureSpec);
    }

    public void releaseResources() {
        if (marqueeTextView != null) {
            if (viewFlipper != null) {
                viewFlipper.stopFlipping();
                viewFlipper.removeAllViews();
                viewFlipper = null;
            }
            marqueeTextView = null;
        }
    }
}

5、MarqueeTextViewClickListener

package com.youjiakeji.helloaa.tools;

import android.view.View;

/**
 * Created by administrator on 2016/11/28.
 */

public interface MarqueeTextViewClickListener {
    void onClick(View view, int position);
}

6、slide_in_bottom

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <translate
        android:duration="@android:integer/config_mediumAnimTime"
        android:fromYDelta="50%p"
        android:toYDelta="0" />
    <alpha
        android:duration="@android:integer/config_mediumAnimTime"
        android:fromAlpha="0.0"
        android:toAlpha="1.0" />
</set>

7、slide_out_top

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <translate
        android:duration="@android:integer/config_mediumAnimTime"
        android:fromYDelta="0"
        android:toYDelta="-50%p" />
    <alpha
        android:duration="@android:integer/config_mediumAnimTime"
        android:fromAlpha="1.0"
        android:toAlpha="0.0" />
</set>

8、marquee_textview_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:orientation="horizontal"
    >

    <ViewFlipper
        android:id="@+id/viewFlipper"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        >
    </ViewFlipper>
</LinearLayout>