android自定义view解决textview显示排版的问题

public class MyTextView extends TextView {

private int textSize = 25;
private int textColor = R.color.black;
private String text;
private Paint paint;
private boolean hasDrawed = false;
private List<String> lines;

public DiskNameTextView(Context context, AttributeSet attrs) {
super(context, attrs);
textSize = attrs.getAttributeIntValue(
"http://schemas.android.com/apk/res/android", "textSize", 28);
textColor = attrs.getAttributeIntValue(
"http://schemas.android.com/apk/res/android", "textColor", R.color.black);
paint = new Paint();
paint.setTextSize(textSize);
paint.setColor(textColor);
paint.setStyle(Style.FILL);
paint.setAntiAlias(true);
}

@SuppressLint("DrawAllocation")
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (text != null && !text.trim().equals("")) {
if(lines != null) {				//先把每行文字保存起来，重画的时候加快速度
for(int i=0; i<lines.size(); i++) {
canvas.drawText(lines.get(i), 0, (i+1) * textSize, paint);
}
return;
}
int viewWidth = this.getWidth();									// 得到view的宽度
int textWidth = (int) paint.measureText(text, 0, text.length());	// 得到text的宽度
int line = (int) Math.ceil(textWidth / viewWidth) + 1;				//得到行数
if(!hasDrawed) {	//通过行数设置view的高度，最后加的1/2行高是为了把p、j这种跨行的字母显示完整
this.setLayoutParams(new LayoutParams(viewWidth, textSize * line + textSize / 2));
}
if (textWidth < viewWidth) {
canvas.drawText(text, 0, textSize, paint);
} else {
int currIndex = 0;
int lineNum = 1;
String lastLine = "";
lines = new ArrayList<String>();
int lineWords = (int) ((float)text.length() / ((float) textWidth / (float) viewWidth + 2));
for (int i = lineWords; i < text.length(); i++) {
String subStr = text.substring(currIndex, i);
int width = (int) paint.measureText(subStr, 0, subStr.length());
if (width < viewWidth) {
lastLine = subStr;
if (i == text.length() - 1) {
lastLine = text.substring(currIndex, ++i);
canvas.drawText(lastLine, 0, lineNum * textSize, paint);
lines.add(lastLine);
}
continue;
} else {
canvas.drawText(lastLine, 0, lineNum * textSize, paint);
lines.add(lastLine);
currIndex = i - 1;
lineNum++;
i--;
if(i + lineWords < text.length())
i += lineWords;
}
}
hasDrawed = true;
}
}

}

public String getText() {
return text;
}

public void setText(String text) {
this.text = text;
hasDrawed = false;
invalidate();
}

}