Create class and extend View. Then create Listener interface for your class.
public class WaveformCls extends View {
public interface WaveformListener {
public void waveformTouchStart(float x);
public void waveformTouchMove(float x);
public void waveformTouchEnd();
public void waveformFling(float x);
public void waveformDraw();
};
Create Paint object as per your requirement.
Create one method which is initialized all Paint object.
public WaveformView(Context context, AttributeSet attrs) {
super(context, attrs);
// We don't want keys, the markers get these
setFocusable(false);
mGridPaint = new Paint();
mGridPaint.setAntiAlias(false);
mGridPaint.setColor(
getResources().getColor(R.drawable.grid_line));
mSelectedLinePaint = new Paint();
mSelectedLinePaint.setAntiAlias(false);
mSelectedLinePaint.setColor(
getResources().getColor(R.drawable.waveform_selected));
mUnselectedLinePaint = new Paint();
mUnselectedLinePaint.setAntiAlias(false);
mUnselectedLinePaint.setColor(
getResources().getColor(R.drawable.waveform_unselected));
mUnselectedBkgndLinePaint = new Paint();
mUnselectedBkgndLinePaint.setAntiAlias(false);
mUnselectedBkgndLinePaint.setColor(
getResources().getColor(
R.drawable.waveform_unselected_bkgnd_overlay));
mBorderLinePaint = new Paint();
mBorderLinePaint.setAntiAlias(true);
mBorderLinePaint.setStrokeWidth(1.5f);
mBorderLinePaint.setPathEffect(
new DashPathEffect(new float[] { 3.0f, 2.0f }, 0.0f));
mBorderLinePaint.setColor(
getResources().getColor(R.drawable.selection_border));
mPlaybackLinePaint = new Paint();
mPlaybackLinePaint.setAntiAlias(false);
mPlaybackLinePaint.setColor(
getResources().getColor(R.drawable.playback_indicator));
mTimecodePaint = new Paint();
mTimecodePaint.setTextSize(12);
mTimecodePaint.setAntiAlias(true);
mTimecodePaint.setColor(
getResources().getColor(R.drawable.timecode));
mTimecodePaint.setShadowLayer(
2, 1, 1,
getResources().getColor(R.drawable.timecode_shadow));
mGestureDetector = new GestureDetector(
context,
new GestureDetector.SimpleOnGestureListener() {
public boolean onFling(
MotionEvent e1, MotionEvent e2, float vx, float vy) {
mListener.waveformFling(vx);
return true;
}
});
mSoundFile = null;
mLenByZoomLevel = null;
mValuesByZoomLevel = null;
mHeightsAtThisZoomLevel = null;
mOffset = 0;
mPlaybackPos = -1;
mSelectionStart = 0;
mSelectionEnd = 0;
mDensity = 1.0f;
mInitialized = false;
}
You need to override onTouchEvent
@Override
public boolean onTouchEvent(MotionEvent event) {
if (mGestureDetector.onTouchEvent(event)) {
return true;
}
switch(event.getAction()) {
case MotionEvent.ACTION_DOWN:
mListener.waveformTouchStart(event.getX());
break;
case MotionEvent.ACTION_MOVE:
mListener.waveformTouchMove(event.getX());
break;
case MotionEvent.ACTION_UP:
mListener.waveformTouchEnd();
break;
}
return true;
}
public void setSoundFile(CheapSoundFile soundFile) {
mSoundFile = soundFile;
mSampleRate = mSoundFile.getSampleRate();
mSamplesPerFrame = mSoundFile.getSamplesPerFrame();
computeDoublesForAllZoomLevels();
mHeightsAtThisZoomLevel = null;
}
override the draw method which draw wave on your screen.
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (mSoundFile == null)
return;
if (mHeightsAtThisZoomLevel == null)
computeIntsForThisZoomLevel();
// Draw waveform
int measuredWidth = getMeasuredWidth();
int measuredHeight = getMeasuredHeight();
int start = mOffset;
int width = mHeightsAtThisZoomLevel.length - start;
int ctr = measuredHeight / 2;
if (width > measuredWidth)
width = measuredWidth;
// Draw grid
double onePixelInSecs = pixelsToSeconds(1);
boolean onlyEveryFiveSecs = (onePixelInSecs > 1.0 / 50.0);
double fractionalSecs = mOffset * onePixelInSecs;
int integerSecs = (int) fractionalSecs;
int i = 0;
while (i < width) {
i++;
fractionalSecs += onePixelInSecs;
int integerSecsNew = (int) fractionalSecs;
if (integerSecsNew != integerSecs) {
integerSecs = integerSecsNew;
if (!onlyEveryFiveSecs || 0 == (integerSecs % 5)) {
canvas.drawLine(i, 0, i, measuredHeight, mGridPaint);
}
}
}
// Draw waveform
for (i = 0; i < width; i++) {
Paint paint;
if (i + start >= mSelectionStart &&
i + start < mSelectionEnd) {
paint = mSelectedLinePaint;
} else {
drawWaveformLine(canvas, i, 0, measuredHeight,
mUnselectedBkgndLinePaint);
paint = mUnselectedLinePaint;
}
drawWaveformLine(
canvas, i,
ctr - mHeightsAtThisZoomLevel[start + i],
ctr + 1 + mHeightsAtThisZoomLevel[start + i],
paint);
if (i + start == mPlaybackPos) {
canvas.drawLine(i, 0, i, measuredHeight, mPlaybackLinePaint);
}
}
// If we can see the right edge of the waveform, draw the
// non-waveform area to the right as unselected
for (i = width; i < measuredWidth; i++) {
drawWaveformLine(canvas, i, 0, measuredHeight,
mUnselectedBkgndLinePaint);
}
// Draw borders
canvas.drawLine(
mSelectionStart - mOffset + 0.5f, 30,
mSelectionStart - mOffset + 0.5f, measuredHeight,
mBorderLinePaint);
canvas.drawLine(
mSelectionEnd - mOffset + 0.5f, 0,
mSelectionEnd - mOffset + 0.5f, measuredHeight - 30,
mBorderLinePaint);
// Draw timecode
double timecodeIntervalSecs = 1.0;
if (timecodeIntervalSecs / onePixelInSecs < 50) {
timecodeIntervalSecs = 5.0;
}
if (timecodeIntervalSecs / onePixelInSecs < 50) {
timecodeIntervalSecs = 15.0;
}
// Draw grid
fractionalSecs = mOffset * onePixelInSecs;
int integerTimecode = (int) (fractionalSecs / timecodeIntervalSecs);
i = 0;
while (i < width) {
i++;
fractionalSecs += onePixelInSecs;
integerSecs = (int) fractionalSecs;
int integerTimecodeNew = (int) (fractionalSecs /
timecodeIntervalSecs);
if (integerTimecodeNew != integerTimecode) {
integerTimecode = integerTimecodeNew;
// Turn, e.g. 67 seconds into "1:07"
String timecodeMinutes = "" + (integerSecs / 60);
String timecodeSeconds = "" + (integerSecs % 60);
if ((integerSecs % 60) < 10) {
timecodeSeconds = "0" + timecodeSeconds;
}
String timecodeStr = timecodeMinutes + ":" + timecodeSeconds;
float offset = (float) (
0.5 * mTimecodePaint.measureText(timecodeStr));
canvas.drawText(timecodeStr,
i - offset,
(int)(12 * mDensity),
mTimecodePaint);
}
}
if (mListener != null) {
mListener.waveformDraw();
}
}
Here is complete source code of Rindroid which is useful for you
Source code for waveform
