AutoTextView实现文字自动翻转效果

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​编辑

效果图如上

代码如下：

AutoTextView

package com.jky.mobilebzt.view;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Camera;
import android.graphics.Matrix;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.View;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.Animation;
import android.view.animation.Transformation;
import android.widget.TextSwitcher;
import android.widget.TextView;
import android.widget.ViewSwitcher;

import com.jky.mobilebzt.R;


public class AutoTextView extends TextSwitcher implements
        ViewSwitcher.ViewFactory {

    private float mHeight;
    private Context mContext;
    //mInUp,mOutUp分别构成向下翻页的进出动画
    private Rotate3dAnimation mInUp;
    private Rotate3dAnimation mOutUp;

    //mInDown,mOutDown分别构成向下翻页的进出动画
    private Rotate3dAnimation mInDown;
    private Rotate3dAnimation mOutDown;

    public AutoTextView(Context context) {
        this(context, null);
    }

    public AutoTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.auto3d);
        mHeight = a.getDimension(R.styleable.auto3d_textSize, 36);
        a.recycle();
        mContext = context;
        init();
    }

    private void init() {
        setFactory(this);
        mInUp = createAnim(-90, 0, true, true);
        mOutUp = createAnim(0, 90, false, true);
        mInDown = createAnim(90, 0, true, false);
        mOutDown = createAnim(0, -90, false, false);
        //TextSwitcher主要用于文件切换，比如 从文字A 切换到 文字 B，
        //setInAnimation()后，A将执行inAnimation，
        //setOutAnimation()后，B将执行OutAnimation

        //初始化翻转
//        setInAnimation(mInUp);
//        setOutAnimation(mOutUp);
    }

    private Rotate3dAnimation createAnim(float start, float end, boolean turnIn, boolean turnUp) {
        final Rotate3dAnimation rotation = new Rotate3dAnimation(start, end, turnIn, turnUp);
        rotation.setDuration(800);
        rotation.setFillAfter(false);
        rotation.setInterpolator(new AccelerateInterpolator());
        return rotation;
    }

    //这里返回的TextView，就是我们看到的View
    @Override
    public View makeView() {
        TextView t = new TextView(mContext);
//        t.setGravity(Gravity.CENTER);
        t.setTextSize(mHeight);
//        t.setTextColor(Resources.getSystem().getColor(android.R.color.black));
        t.setTextColor(mContext.getResources().getColor(R.color.white));
        t.setTextSize(13);
//        t.setGravity(Gravity.CENTER_VERTICAL);
        t.setPadding(0,15,0,15);
        t.setMaxLines(1);
        t.setEllipsize(TextUtils.TruncateAt.END);
        return t;
    }

    //定义动作，向下滚动翻页
    public void previous() {
        if (getInAnimation() != mInDown) {
            setInAnimation(mInDown);
        }
        if (getOutAnimation() != mOutDown) {
            setOutAnimation(mOutDown);
        }
    }

    //定义动作，向上滚动翻页
    public void next() {
        if (getInAnimation() != mInUp) {
            setInAnimation(mInUp);
        }
        if (getOutAnimation() != mOutUp) {
            setOutAnimation(mOutUp);
        }
    }

    class Rotate3dAnimation extends Animation {
        private final float mFromDegrees;
        private final float mToDegrees;
        private float mCenterX;
        private float mCenterY;
        private final boolean mTurnIn;
        private final boolean mTurnUp;
        private Camera mCamera;

        public Rotate3dAnimation(float fromDegrees, float toDegrees, boolean turnIn, boolean turnUp) {
            mFromDegrees = fromDegrees;
            mToDegrees = toDegrees;
            mTurnIn = turnIn;
            mTurnUp = turnUp;
        }

        @Override
        public void initialize(int width, int height, int parentWidth, int parentHeight) {
            super.initialize(width, height, parentWidth, parentHeight);
            mCamera = new Camera();
            mCenterY = getHeight() / 2;
            mCenterX = getWidth() / 2;
        }

        @Override
        protected void applyTransformation(float interpolatedTime, Transformation t) {
            final float fromDegrees = mFromDegrees;
            float degrees = fromDegrees + ((mToDegrees - fromDegrees) * interpolatedTime);

            final float centerX = mCenterX;
            final float centerY = mCenterY;
            final Camera camera = mCamera;
            final int derection = mTurnUp ? 1 : -1;

            final Matrix matrix = t.getMatrix();

            camera.save();
            if (mTurnIn) {
                camera.translate(0.0f, derection * mCenterY * (interpolatedTime - 1.0f), 0.0f);
            } else {
                camera.translate(0.0f, derection * mCenterY * (interpolatedTime), 0.0f);
            }
            camera.rotateX(degrees);
            camera.getMatrix(matrix);
            camera.restore();

            matrix.preTranslate(-centerX, -centerY);
            matrix.postTranslate(centerX, centerY);
        }
    }
}

attrs.xml

   <declare-styleable name="auto3d">
        <attr name="textSize" format="dimension" />
    </declare-styleable>

xml

        <com.xx.xx.view.AutoTextView
                    android:id="@+id/atv_auto_qy"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_marginTop="@dimen/margin_5" />

activity

    private void showQyInfo() {
//        qyPowers.clear();

        isShowQyView = true;
        mQyInfoView.setVisibility(View.VISIBLE);
        if(timer == null){
            String[] qyinfo = context.getResources().getStringArray(R.array.qy_power);
            qyPowers = Arrays.asList(qyinfo);
            timer = new Timer();
            timer.schedule(timerTask, 100, 3000);
            powerPosition = 0;
        }
    }

    //计时
    TimerTask timerTask = new TimerTask() {
        @Override
        public void run() {

            if(isShowQyView) {
                Message message = new Message();
                message.what = 0x001;
                handler.sendMessage(message);
            }
        }
    };
    final Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case 0x001:
                    atvQy.next();
                    atvQy.setText(qyPowers.get(powerPosition));
                    powerPosition ++;
                    powerPosition = powerPosition % 3;

            }
        }


    };

strings.xml

<array name="qy_power">
        <item>8000＋本建筑行业标准在线查看</item>
        <item>随时创建反馈，企业专家、云服务专家组、标准规范起草人为您解答</item>
        <item>移动课堂专享课程免费学习</item>
    </array>