自定义文字跑马灯效果(滚动文字)

自定义文字跑马灯效果(滚动文字)

Android系统TextView跑马灯限制过多(需有焦点和文字超长)

MarqueeTextView

设置步长(滚动速度)即可滚动

public class MarqueeTextView extends AppCompatTextView {

    private static final int PFS = 24;//刷新率
    private int textWidth;//文字长度
    private int mStep = -5;//速度，负数左移，正数右移。
    private int mOffsetX = 0;//偏移量
    private int mDistance = 100;//文件重复出现间距

    private Timer mTimer;//定时器
    private Rect mTextRect;//文字占位矩阵
    private TimerTask mTimerTask;//定时任务
    private boolean isPressPause = true;//是否按压暂停
    private boolean isStop = false;
    private boolean isSingle = false;

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

    public MarqueeTextView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        mTextRect = new Rect();
        mTimer = new Timer();
        mTimerTask = new ScrollTask();
        mTimer.schedule(mTimerTask, 0, 1000 / PFS);
        setDistance(100);
        setSingle(false);
    }

    public MarqueeTextView(Context context, AttributeSet attrs) {
        this(context, attrs, android.R.attr.textViewStyle);
    }

    private class ScrollTask extends TimerTask {
        @Override
        public void run() {
            if (mStep != 0 && !isStop) {
                mOffsetX += mStep;
                int maxW = textWidth + mDistance;
                mOffsetX = mOffsetX % (maxW);
                postInvalidate();
            }
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {
        if (mStep == 0) {
            super.onDraw(canvas);
        } else {
            String mText = getText().toString();
            TextPaint textPaint = getPaint();
            textPaint.setColor(getCurrentTextColor());
            textPaint.getTextBounds(mText, 0, mText.length(), mTextRect);
            float mTextCenterVerticalToBaseLine =
                    (-textPaint.ascent() + textPaint.descent()) / 2 - textPaint.descent();
            int width = getWidth();
            textWidth = mTextRect.width();
            boolean isLeft = mStep < 0;
            float y = (getHeight() >> 1) + mTextCenterVerticalToBaseLine;
            if (isSingle) {
                mDistance = width;
                canvas.drawText(mText, mOffsetX + (isLeft ? mDistance : -textWidth), y, textPaint);
            } else {
                int w = textWidth + mDistance;
                int size = width / w + 1;
                canvas.drawText(mText, mOffsetX + (isLeft ? 0 : width - textWidth), y, textPaint);
                for (int i = 1; i <= size; i++) {
                    int offset = w * i;
                    canvas.drawText(mText, mOffsetX + (isLeft ? offset : width - textWidth - offset), y, textPaint);
                }
            }
        }
    }

    @SuppressLint("ClickableViewAccessibility")
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (isPressPause && event != null) {
            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    setStop(true);
                    break;
                case MotionEvent.ACTION_UP:
                case MotionEvent.ACTION_CANCEL:
                    setStop(false);
                    break;
            }
            return true;
        }
        return super.onTouchEvent(event);
    }

    @Override
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        if (mTimerTask != null) {
            mTimerTask.cancel();
            mTimerTask = null;
        }
        if (mTimer != null) {
            mTimer.cancel();
            mTimer = null;
        }
        mTextRect = null;
    }

    public void setStep(int step) {
        mOffsetX = 0;
        mStep = step;
        postInvalidate();
    }

    public int getStep() {
        return mStep;
    }

    public void setDistance(int distance) {
        if (!isSingle){
            mDistance = distance;
            lastDistance = mDistance;
        }
  }

    public void setPressPause(boolean isPressPause) {
        this.isPressPause = isPressPause;
    }

    public void setStop(boolean stop) {
        isStop = stop;
    }

    private int lastDistance = 0;

    public void setSingle(boolean single) {
        mOffsetX = 0;
        isSingle = single;
        if (single) {
            lastDistance = mDistance;
        } else {
            mDistance = lastDistance;
        }
        postInvalidate();
    }

    public boolean isStop() {
        return isStop;
    }

    public boolean isSingle() {
        return isSingle;
    }
}

效果图

示例

1、布局文件

2、Activity

public class MainActivity extends AppCompatActivity {

    private TextView tvStep;
    private MarqueeTextView tv_1;
    private MarqueeTextView tv_2;
    private TextView tvDistance;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tv_1 = findViewById(R.id.marquee_tv_1);
        tv_2 = findViewById(R.id.marquee_tv_2);
        tv_2.setSingle(true);
        Button btnSingle = findViewById(R.id.btn_single);
        btnSingle.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                setSingle();
            }
        });
        SeekBar seekStep = findViewById(R.id.seek_step);
        SeekBar seekDistance = findViewById(R.id.seek_distance);
        tvStep = findViewById(R.id.tv_step);
        tvDistance = findViewById(R.id.tv_distance);
        seekDistance.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                setDistance(progress);
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {

            }
        });
        seekStep.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                setStep(progress);
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {

            }
        });
    }

    public void setStep(int step) {
        tvStep.setText(String.valueOf(step));
        tv_1.setStep(step);
        tv_2.setStep(step);
    }

    public void setSingle() {
        tv_1.setSingle(!tv_1.isSingle());
        tv_2.setSingle(!tv_2.isSingle());
    }

    public void setDistance(int distance) {
        tvDistance.setText(String.valueOf(distance));
        tv_1.setDistance(distance);
        tv_2.setDistance(distance);
    }
}