如何布局文本以围绕图像流动

你能告诉我是否有一种方法来布局文本 围绕图像？ 像这样：

------  text text text
|    |  text text text
-----   text text text
text text text text
text text text text

我已经收到一位 Android 开发者关于这个问题的回复。但我不确定他说做我自己的 TextView 版本是什么意思？感谢您的任何提示。

2010 年 2 月 8 日星期一晚上 11:05，Romain Guy 写道：

Hi,

仅使用提供的小部件和布局是不可能实现这一点的。你 可以编写您自己的 TextView 版本来执行此操作，但不应该 难的。

现在可以了，但仅适用于版本高于或等于 2.2 的手机，方法是使用android.text.style.LeadingMarginSpan.LeadingMarginSpan2API 8 中提供了接口。

这里是article http://dev.androidteam.ru/snippets/textview/leadingmarginspan2，虽然不是英文的，但是你可以直接从下面下载示例的源代码here http://dl.dropbox.com/u/1134234/AndroidTeam/dev/examples/MyLeadingMarginSpan2.zip.

如果您想让您的应用程序与旧设备兼容，您可以显示不同的布局，而无需浮动文本。 这是一个例子：

布局（旧版本的默认布局，将针对新版本以编程方式更改）

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content">
    <ImageView 
            android:id="@+id/thumbnail_view"
            android:src="@drawable/icon"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

    <TextView android:id="@+id/message_view"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_toRightOf="@id/thumbnail_view"
            android:textSize="18sp"
            android:text="@string/text" />
</RelativeLayout>

辅助类

class FlowTextHelper {

    private static boolean mNewClassAvailable;

    static {
        if (Integer.parseInt(Build.VERSION.SDK) >= 8) { // Froyo 2.2, API level 8
           mNewClassAvailable = true;
        }
    }

    public static void tryFlowText(String text, View thumbnailView, TextView messageView, Display display){
        // There is nothing I can do for older versions, so just return
        if(!mNewClassAvailable) return;

        // Get height and width of the image and height of the text line
        thumbnailView.measure(display.getWidth(), display.getHeight());
        int height = thumbnailView.getMeasuredHeight();
        int width = thumbnailView.getMeasuredWidth();
        float textLineHeight = messageView.getPaint().getTextSize();

        // Set the span according to the number of lines and width of the image
        int lines = (int)FloatMath.ceil(height / textLineHeight);
        //For an html text you can use this line: SpannableStringBuilder ss = (SpannableStringBuilder)Html.fromHtml(text);
        SpannableString ss = new SpannableString(text);
        ss.setSpan(new MyLeadingMarginSpan2(lines, width), 0, ss.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
        messageView.setText(ss);

        // Align the text with the image by removing the rule that the text is to the right of the image
        RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams)messageView.getLayoutParams();
        int[]rules = params.getRules();
        rules[RelativeLayout.RIGHT_OF] = 0;
    }
}

MyLeadingMarginSpan2 类（已更新以支持 API 21）

public class MyLeadingMarginSpan2 implements LeadingMarginSpan2 {
    private int margin;
    private int lines;
    private boolean wasDrawCalled = false;
    private int drawLineCount = 0;

    public MyLeadingMarginSpan2(int lines, int margin) {
        this.margin = margin;
        this.lines = lines;
    }

    @Override
    public int getLeadingMargin(boolean first) {
        boolean isFirstMargin = first;
        // a different algorithm for api 21+
        if (Build.VERSION.SDK_INT >= 21) {
            this.drawLineCount = this.wasDrawCalled ? this.drawLineCount + 1 : 0;
            this.wasDrawCalled = false;
            isFirstMargin = this.drawLineCount <= this.lines;
        }

        return isFirstMargin ? this.margin : 0;
    }

    @Override
    public void drawLeadingMargin(Canvas c, Paint p, int x, int dir, int top, int baseline, int bottom, CharSequence text, int start, int end, boolean first, Layout layout) {
        this.wasDrawCalled = true;
    }

    @Override
    public int getLeadingMarginLineCount() {
        return this.lines;
    }
}

使用示例

ImageView thumbnailView = (ImageView) findViewById(R.id.thumbnail_view);
TextView messageView = (TextView) findViewById(R.id.message_view);
String text = getString(R.string.text);

Display display = getWindowManager().getDefaultDisplay();
FlowTextHelper.tryFlowText(text, thumbnailView, messageView, display);

This is how the application looks on the Android 2.2 device:

这是针对 Android 2.1 设备的：