package com.stackdump.bitmapautolinefeed;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.text.Layout;
import android.text.StaticLayout;
import android.text.TextPaint;
import android.util.Log;
import android.view.Display;
import android.view.View;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import com.stackdump.bitmapautolinefeed.utils.SurfaceViewUtils;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
//屏幕的宽度
private int mDisplayX;
//屏幕的高度
private int mDisplayY;
private EditText mEditText;
private ImageView mImage;
private Button mBtn;
private TextPaint mPaint;
//需要生成的图片
private Bitmap mBitmap;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mEditText = (EditText)findViewById(R.id.text);
mImage = (ImageView) findViewById(R.id.image);
mBtn = (Button) findViewById(R.id.btn);
//获取屏幕的宽度和高度，获取的宽度用于计算何时自动换行
WindowManager manager = (WindowManager)getSystemService(Context.WINDOW_SERVICE);
Display display = manager.getDefaultDisplay();
Point size = new Point();
display.getSize(size);
mDisplayX = size.x;
mDisplayY = size.y;
mBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//存在内存泄露的风险，需自行优化
new AsyncTask<Void, Void, Boolean>() {
@Override
protected void onPreExecute() {
}
@Override
protected Boolean doInBackground(Void... unused) {
Log.d("info","doInBackground");
return saveBmp(mEditText.getText().toString());
}
@Override
protected void onProgressUpdate(Void... unused) {
}
@Override
protected void onPostExecute(Boolean result) {
Log.d("info","getFilesDir:"+getFilesDir());//存储在内置存储
Log.d("info","getExternalStorageDirectory:"+Environment.getExternalStorageDirectory());//外置存储路径
Bitmap bmp = getLoacalBitmap(getFilesDir()+"/siteName.bmp");
if(bmp != null) {
mImage.setImageBitmap(bmp);
}
}
}.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
}
});
}
private boolean saveBmp(String text) {
try {
initializePaint();
//文字是单行时的总宽度（先计算单行的长度）
int textWidth;
//文字是单行时的总高度（先计算单行的高度）
int textHeight;
textWidth = (int) mPaint.measureText(text);
Paint.FontMetrics fm = mPaint.getFontMetrics();
textHeight = (int) Math.ceil(fm.bottom - fm.top);
Log.d("info","textWidth:"+textWidth+" textHeight:"+textHeight);
Log.d("info","mDisplayX:"+mDisplayX+" mDisplayY:"+mDisplayY);
mBitmap = getNewBitMap(text, textWidth, textHeight, Math.abs(fm.top), mPaint);
saveFileHighQuality(mBitmap);
} catch (StringIndexOutOfBoundsException e) {
return false;
} catch (Exception e) {
return false;
}
return true;
}
public Bitmap getNewBitMap(String text, int textWidth, int textHeight, float top, TextPaint textPaint) {
//水平偏移量,设置该值，文字可向右偏移一定距离
int horizontalOffset = 60;
int verticalOffset = 60;
//The text may be more than one line,so calculate the number of rows
int rows = textWidth / (mDisplayX-horizontalOffset);
rows = (textWidth % (mDisplayX-horizontalOffset) > 0 ) ? rows + 1 : rows;
//
int bmpWidth = rows > 1 ? mDisplayX : (textWidth+horizontalOffset);
int bmpHeight = Math.min(mDisplayY, textHeight*rows+verticalOffset);
Bitmap newBitmap = Bitmap.createBitmap(bmpWidth,bmpHeight, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(newBitmap);
canvas.drawBitmap(newBitmap, 0, top, textPaint);
canvas.translate(horizontalOffset, verticalOffset);
/*
参数含义：
1.字符串子资源
2 .画笔对象
3.layout的宽度，字符串超出宽度时自动换行。(屏幕总宽度-水平平移量就是layout宽度)
4.layout的样式，有ALIGN_CENTER， ALIGN_NORMAL， ALIGN_OPPOSITE 三种。
5.相对行间距，相对字体大小，1.5f表示行间距为1.5倍的字体高度。
6.相对行间距，0表示0个像素。
实际行间距等于这两者的和。
7.还不知道是什么意思，参数名是boolean includepad。
需要指出的是这个layout是默认画在Canvas的(0,0)点的，如果需要调整位置只能在draw之前移Canvas的起始坐标
canvas.translate(x,y);
*/
StaticLayout sl= new StaticLayout(text, textPaint, mDisplayX-horizontalOffset, Layout.Alignment.ALIGN_NORMAL, 1.0f, 0.0f, false);
sl.draw(canvas);
return newBitmap;
}
private void initializePaint() {
mPaint = new TextPaint();
//抗锯齿,设置为true，边界明显变模糊
mPaint.setAntiAlias(true);
//防抖动,设置为true，边界明显变模糊
mPaint.setDither(true);
mPaint.setColor(Color.RED);
//透明度0-255,数值越小越透明
mPaint.setAlpha(255);
mPaint.setTextSize(100);
}
private boolean saveFileHighQuality(Bitmap bm) {
if (!Environment.MEDIA_MOUNTED.equals(Environment
.getExternalStorageState())) {
return false;
}
FileOutputStream out = null;
try {
out = openFileOutput("siteName.bmp", Context.MODE_PRIVATE);
int w = bm.getWidth();
int h = bm.getHeight();
int[] pixels = new int[w * h];
bm.getPixels(pixels, 0, w, 0, 0, w, h);
byte[] rgb = SurfaceViewUtils.addBMP_RGB_888(pixels, w, h);
byte[] header = SurfaceViewUtils.addBMPImageHeader(rgb.length);
byte[] infos = SurfaceViewUtils.addBMPImageInfosHeader(w, h);
byte[] buffer = new byte[54 + rgb.length];
System.arraycopy(header, 0, buffer, 0, header.length);
System.arraycopy(infos, 0, buffer, 14, infos.length);
System.arraycopy(rgb, 0, buffer, 54, rgb.length);
out.write(buffer);
//将输入流和输出流中的缓冲进行刷新，使缓冲区中的元素即时做输入和输出，而不必等缓冲区满
out.flush();
} catch (FileNotFoundException e) {
return false;
} catch (IOException e) {
return false;
} catch (Exception e) {
return false;
} finally {
if (out != null) {
try {
out.close();
} catch (IOException e) {
// TODO Auto-generated catch block
}
}
if (!mBitmap.isRecycled()) {
mBitmap.recycle();
//作用只是提醒或告诉虚拟机，希望进行一次垃圾回收。
//至于什么时候进行回收还是取决于虚拟机，而且也不能保证一定进行回收（如果-XX:+DisableExplicitGC设置成true，则不会进行回收）
System.gc();
}
}
return true;
}
/**
* 加载本地图片
* 本地图片路径
* @param path
* @return
*/
public static Bitmap getLoacalBitmap(String path) {
try {
FileInputStream fis = new FileInputStream(path);
return BitmapFactory.decodeStream(fis);
} catch (FileNotFoundException e) {
e.printStackTrace();
return null;
}
}
/**
* 从服务器取图片
* @param url
* @return
*/
public static Bitmap getHttpBitmap(String url) {
URL myFileUrl = null;
Bitmap bitmap = null;
try {
Log.d("info", url);
myFileUrl = new URL(url);
} catch (MalformedURLException e) {
e.printStackTrace();
}
try {
HttpURLConnection conn = (HttpURLConnection) myFileUrl.openConnection();
conn.setConnectTimeout(10);
conn.setReadTimeout(10);
conn.setDoInput(true);
conn.connect();
InputStream is = conn.getInputStream();
bitmap = BitmapFactory.decodeStream(is);
is.close();
} catch (IOException e) {
e.printStackTrace();
}
return bitmap;
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<Button
android:id="@+id/btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="click"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<EditText
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/colorAccent"
app:layout_constraintLeft_toRightOf="@+id/btn"/>
<ImageView
android:id="@+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="@+id/btn"
/>
</androidx.constraintlayout.widget.ConstraintLayout>
效果：
1.单行且无平移：
2.多行且无平移
3.单行且有平移：
4.多行且有平移：
0