适配完结篇三 - 超稳定的values-wXXXdp适配方案(原创)

# 参考公式
# 假定基准宽度为1280
x1 = 目标宽度(dp) / 1280
x2 = 2 * x1
x4 = 4 * x1
x6 = 6 * x1
...

$ ls
values-w1024dp/  values-w320dp/  values-w640dp/  values-w768dp/  values-w852dp/
values-w1280dp/  values-w480dp/  values-w698dp/  ... ... ...

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <dimen name="x2">1dp</dimen>
    <dimen name="x4">2dp</dimen>
    <dimen name="x6">3dp</dimen>
    <dimen name="x8">4dp</dimen>
    ```
    ```
    <dimen name="x1276">638dp</dimen>
    <dimen name="x1278">639dp</dimen>
    <dimen name="x1280">640dp</dimen>
</resources>

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;

/**
 * 辅助生成资源文件
 * 
 * @author leiTKai
 */
public class GenerateValueFiles {
    private static final String dirStr = "./res";
    private static final String FILE_NAME = "precent_width.xml";
    private static final String TEMPLATE = "    <dimen name=\"x%d\">%sdp</dimen>\n";
    private static final String VALUE_TEMPLATE = "values-w%ddp";

    private final int mBaseWidth;
    private final String mSupportStr;

    /**
     * constructor
     * 
     * @param baseX
     *            基准宽
     * @param supportStr
     */
    public GenerateValueFiles(int baseX, String supportStr) {
        this.mBaseWidth = baseX;
        this.mSupportStr = supportStr;

        System.out.println("baseW: " + this.mBaseWidth);
        System.out.println("supportStr: " + this.mSupportStr);

        File dir = new File(dirStr);
        if (!dir.exists())
            dir.mkdir();
        System.out.print("FileDir: " + dir.getAbsoluteFile());
    }

    public void generate() {
        for (String val : mSupportStr.split(",")) {
            try {
                generateXmlFile(Integer.parseInt(val));
            } catch (IOException e) {
                e.printStackTrace();
                break;
            }
        }
    }

    private void generateXmlFile(final int smallestWidth) throws IOException {
        final File fileDir = new File(dirStr + File.separator
                + String.format(VALUE_TEMPLATE, smallestWidth));
        fileDir.mkdir();

        final File file = new File(fileDir, FILE_NAME);
        Writer writer = new BufferedWriter(new OutputStreamWriter(
                new FileOutputStream(file), "UTF-8"));
        writeContent(writer, mBaseWidth, smallestWidth);
        writer.close();
    }

    private static void writeContent(Writer writer, final int baseLength,
            final int totalLength) throws IOException {
        writer.write("<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
        writer.write("<resources>\n");
        float cell = (float) totalLength / baseLength;
        for (int i = 2; i < baseLength; i+=2) {
            writer.write(String.format(TEMPLATE, i, float2String(cell * i)));
        }
        writer.write(String.format(TEMPLATE, baseLength,
                String.valueOf(totalLength)));
        writer.write("</resources>");
    }

    /**
     * 如果float类型没有小数部分则不输出小数
     * 
     * @param f
     * @return
     */
    private static String float2String(float f) {
        if (Math.round(f) == f) {
            return String.valueOf((int) f);
        }
        return String.format("%.1f", f);
    }

    public static void main(String[] args) {
        int baseW = 1280;
        String addition = "320,480,532,640,698,732,768,800,852,912,960,1024,1280";
        if (args.length == 1) {
            addition = args[0];
        } else if (args.length == 2) {
            baseW = Integer.parseInt(args[0]);
            addition = args[1];
        }
        new GenerateValueFiles(baseW, addition).generate();
    }
}