在Android中对齐文本

Question

我需要说明一些文本（RTL），这是S1来自服务器的字符串（）。但是a TextView不能证明文本的正确性，因此我必须使用a
WebView，现在必须创建一个HTML文件，其中将显示S1。然后，我将该html文件的地址存储在数据库中，然后显示该html文件。我曾经在SO上看到过这个问题，并且很多人建议使用3rd
party库，但我尝试了所有这些方法，但都无济于事（它们在90％的场景中都有效，但并不完全可靠）。

我觉得这种方法似乎很复杂，我想知道是否有更好的方法？

Answer 1

我使用以下代码来回答非常需要此主题的人们，并创建在每个显示中都支持的公式。

    public class TextJustify {

final static String SYSTEM_NEWLINE = "\n";
final static float COMPLEXITY = 5.12f; // Reducing this will increase
                                        // efficiency but will decrease
                                        // effectiveness
final static Paint p = new Paint();

/* @author Mathew Kurian */

public static void run(final TextView tv, float origWidth, int paddingLeft, int paddingRight, int marginLeft, int marginRight) {


    origWidth-= paddingRight+marginRight+paddingLeft+marginLeft;
    String s = tv.getText().toString();
    p.setTypeface(tv.getTypeface());
    String[] splits = s.split(SYSTEM_NEWLINE);
    float width = origWidth - 5;
    for (int x = 0; x < splits.length; x++)
        if (p.measureText(splits[x]) > width) {
            splits[x] = wrap(splits[x], width, p);
            String[] microSplits = splits[x].split(SYSTEM_NEWLINE);
            for (int y = 0; y < microSplits.length - 1; y++)
                microSplits[y] = justify(removeLast(microSplits[y], " "),
                        width, p);
            StringBuilder smb_internal = new StringBuilder();
            for (int z = 0; z < microSplits.length; z++)
                smb_internal.append(microSplits[z]
                        + ((z + 1 < microSplits.length) ? SYSTEM_NEWLINE
                                : ""));
            splits[x] = smb_internal.toString();
        }
    final StringBuilder smb = new StringBuilder();
    for (String cleaned : splits)
        smb.append(cleaned + SYSTEM_NEWLINE);
    tv.setGravity(Gravity.RIGHT);
    tv.setText(smb);
}

private static String wrap(String s, float width, Paint p) {
    String[] str = s.split("\\s"); // regex
    StringBuilder smb = new StringBuilder(); // save memory
    smb.append(SYSTEM_NEWLINE);
    for (int x = 0; x < str.length; x++) {
        float length = p.measureText(str[x]);
        String[] pieces = smb.toString().split(SYSTEM_NEWLINE);
        try {
            if (p.measureText(pieces[pieces.length - 1]) + length > width)
                smb.append(SYSTEM_NEWLINE);
        } catch (Exception e) {
        }
        smb.append(str[x] + " ");
    }
    return smb.toString().replaceFirst(SYSTEM_NEWLINE, "");
}

private static String removeLast(String s, String g) {
    if (s.contains(g)) {
        int index = s.lastIndexOf(g);
        int indexEnd = index + g.length();
        if (index == 0)
            return s.substring(1);
        else if (index == s.length() - 1)
            return s.substring(0, index);
        else
            return s.substring(0, index) + s.substring(indexEnd);
    }
    return s;
}

private static String justifyOperation(String s, float width, Paint p) {
    float holder = (float) (COMPLEXITY * Math.random());
    while (s.contains(Float.toString(holder)))
        holder = (float) (COMPLEXITY * Math.random());
    String holder_string = Float.toString(holder);
    float lessThan = width;
    int timeOut = 100;
    int current = 0;
    while (p.measureText(s) < lessThan && current < timeOut) {
        s = s.replaceFirst(" ([^" + holder_string + "])", " "
                + holder_string + "$1");
        lessThan = p.measureText(holder_string) + lessThan
                - p.measureText(" ");
        current++;
    }
    String cleaned = s.replaceAll(holder_string, " ");
    return cleaned;
}

private static String justify(String s, float width, Paint p) {
    while (p.measureText(s) < width) {
        s = justifyOperation(s, width, p);
    }
    return s;
}
  }

为了调用此代码，您必须使用以下代码，我测试了波斯语语言，并且在每种显示和设备上都运行良好。

     public static final int FinallwidthDp  = 320 ;
     public static final int widthJustify  = 223 ;

     DisplayMetrics metrics = new DisplayMetrics();
     getWindowManager().getDefaultDisplay().getMetrics(metrics);
     int widthPixels = metrics.widthPixels;

     float scaleFactor = metrics.density;
     float widthDp = widthPixels / scaleFactor;

     TextView tv = (TextView) findViewById(R.id.textView1);
     ViewGroup.MarginLayoutParams lp1 = (ViewGroup.MarginLayoutParams) tv.getLayoutParams();

     tv.setText(text);
     TextJustify.run(tv,widthDp / FinallwidthDp * widthJustify , tv.getPaddingLeft(),tv.getPaddingRight() , lp1.leftMargin, lp1.rightMargin);

此算法已在各种设备上进行了测试，并且在正常活动（非对话框）和的wrap- content宽度上都可以正常TextView工作，并且可以处理所有的填充和边距。如果对您不利，您可以进行更改，widthJustify直到对您有利为止，希望这一点有用。对于新更新看到这