Files
assistant-android/app/src/main/java/com/gh/common/view/ExpendTextView.java

135 lines
4.5 KiB
Java

package com.gh.common.view;
import android.content.Context;
import android.graphics.Color;
import android.os.Build;
import android.text.Layout;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.text.TextPaint;
import android.text.style.BackgroundColorSpan;
import android.text.style.ClickableSpan;
import android.util.AttributeSet;
import android.view.View;
import androidx.appcompat.widget.AppCompatTextView;
import androidx.core.content.ContextCompat;
import com.gh.common.util.DisplayUtils;
import com.gh.gamecenter.R;
public class ExpendTextView extends AppCompatTextView {
private CharSequence mSnapshotText;
private String mExpendText = "...全文";
private int mMaxLines = 3; // 由于sdk版本限制(getMaxLines) 这里设置默认值
private boolean mInitLayout = false;
private boolean mOpenLayout = false;
private ExpandCallback mExpandCallback;
public ExpendTextView(Context context) {
super(context);
}
public ExpendTextView(Context context, AttributeSet attrs) {
super(context, attrs);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
mMaxLines = getMaxLines();
}
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
if (mInitLayout && !mOpenLayout && getLineCount() > mMaxLines) {
mSnapshotText = getText();
mInitLayout = false;
showExpendButton();
}
}
public void setExpendText(String text) {
this.mExpendText = text;
}
public void setExpandCallback(ExpandCallback callback) {
this.mExpandCallback = callback;
}
@Override
public void setText(CharSequence text, BufferType type) {
mInitLayout = true;
super.setText(text, type);
}
private void showExpendButton() {
Layout layout = getLayout();
int start = layout.getLineStart(0);
int lastLineEnd = layout.getLineEnd(mMaxLines - 1);
int lastLineStart = layout.getLineStart(mMaxLines - 1);
float lastLineRight = layout.getLineRight(mMaxLines - 1);
int viewWidth = getWidth() - getPaddingRight() - getPaddingLeft();
TextPaint paint = getPaint();
float expendTextWidth = paint.measureText(mExpendText);
CharSequence content = mSnapshotText.subSequence(start, lastLineEnd);
if (viewWidth - lastLineRight > expendTextWidth) {
content = content.toString().trim() + mExpendText;
} else {
CharSequence lastText = mSnapshotText.subSequence(lastLineStart, lastLineEnd);
for (int i = lastText.length() - 1; i > 0; i--) {
CharSequence sequence = lastText.subSequence(0, i);
float w = paint.measureText(sequence.toString());
if (viewWidth - w - DisplayUtils.dip2px(5) > expendTextWidth) {
content = mSnapshotText.subSequence(start, lastLineStart + i) + mExpendText;
break;
}
}
}
SpannableStringBuilder msp = new SpannableStringBuilder(mSnapshotText);
int length = msp.length();
int startPosition = content.length() - mExpendText.length();
startPosition = startPosition < 0 ? 0 : startPosition;
msp.replace(startPosition, length, mExpendText);
msp.setSpan(new ClickableSpan() {
@Override
public void updateDrawState(TextPaint ds) {
super.updateDrawState(ds);
ds.setColor(ContextCompat.getColor(getContext(), R.color.theme));
ds.setUnderlineText(false);
}
@Override
public void onClick(View widget) {
mOpenLayout = true;
setMaxLines(Integer.MAX_VALUE);
setText(mSnapshotText);
if (mExpandCallback != null) {
mExpandCallback.onExpand();
}
}
}, startPosition + 3, msp.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
msp.setSpan(new BackgroundColorSpan(Color.WHITE), startPosition, msp.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
setText(msp);
setMovementMethod(CustomLinkMovementMethod.getInstance());
}
public void setExpendMaxLines(int maxLines) {
mMaxLines = maxLines;
setMaxLines(maxLines);
}
public interface ExpandCallback {
void onExpand();
}
}