如何将双精度放入文本编辑对象？我希望在屏幕上包含尽可能多的数字而不排除科学记数法和舍入。例如：
1000900E13 --> 10009E13
1000090E13 --> 10001E13
1000009E13 --> 1E13
我意识到如果我可以计算出适合文本编辑的字符数，我可以解决这个问题，但字符宽度是可变的。
编辑：好的，我现在已经实现了逻辑，但是当我点击界面上的等号时，我收到以下错误：
fatal signal 6 (SIGBART) at 0x000001b0 (code=0)
//This error happens when I call the function, and it not a bug inside the function itself
这是按钮＆＃34; =＆＃34;我的计算器
equal.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
double result;
result = evaluateString.evaluate(string);
string = formatDouble.fmt(result); //omits redundant zeros and decimal point
Typeface tface = disp.getTypeface();
float fsize = disp.getTextSize();
float field_width = disp.getWidth();
//this function is the problem
String show = fillScreen.getLength(fsize, tface, field_width, string);
disp.setText(show);
}
});
这是将双重填充到文本编辑中的实现。
public class fillScreen {
//find proper length
public static String getLength(float fsize, Typeface tface, float field_width, String string) {
int len = 1;
Paint paint = new Paint();
Rect rect = new Rect();
MainActivity.disp.setText("error");
while (true) {
paint.setTypeface(tface);
paint.setTextSize(fsize);
paint.getTextBounds(string, 0, string.length(), rect);
if (rect.width() > field_width)
break;
len++;
}
len = len - 1;
String numbersigns="0.";
for (int i =0; i<len;i++){
numbersigns=numbersigns+"#";
}
numbersigns=numbersigns+"E0";
NumberFormat formatter = new DecimalFormat(numbersigns);
return (formatter.format(Double.parseDouble(string)));
}
}
将6除以6并按下uequals
后的堆栈跟踪07-12 17:12:42.432: I/System.out(6500): string is : 6/6
07-12 17:12:42.436: I/System.out(6500): strings is : 6/6
07-12 17:12:42.436: I/System.out(6500): strings RVP : 66/
07-12 17:12:45.519: D/AudioHardware(154): AudioHardware pcm playback is going to standby.
07-12 17:12:45.519: V/AudioHardware(154): closeMixer_l() mMixerOpenCnt: 1
07-12 17:12:45.519: D/AudioHardware(154): closePcmOut_l() mPcmOpenCnt: 1
07-12 17:12:47.309: D/lights(432): set_light_buttons: color=0xff000000, tlc=0.
07-12 17:13:12.310: I/PowerManagerService(432): Going to sleep due to screen timeout...
07-12 17:13:13.064: D/dalvikvm(432): GC_FOR_ALLOC freed 2400K, 30% free 12448K/17712K, paused 126ms, total 131ms
07-12 17:13:13.067: D/SurfaceFlinger(149): Screen released, type=0 flinger=0x2a007478
07-12 17:13:13.174: I/WindowManager(432): Screenshot Window{4230d070 u0 com.example.test/com.example.test.MainActivity} was all black! mSurfaceLayer=21040 minLayer=21040 maxLayer=21040
07-12 17:13:13.240: D/AccelerometerListener(744): enable(false)
07-12 17:13:13.677: W/ActivityManager(432): Activity pause timeout for ActivityRecord{420b2be8 u0 com.example.test/.MainActivity}
07-12 17:13:18.144: W/ActivityManager(432): Sleep timeout! Sleeping now.
07-12 17:13:18.507: D/dalvikvm(432): GC_FOR_ALLOC freed 1165K, 25% free 13326K/17712K, paused 152ms, total 153ms
07-12 17:13:18.507: I/ActivityManager(432): Start proc com.cyanogenmod.lockclock for broadcast com.cyanogenmod.lockclock/.ClockWidgetProvider: pid=6753 uid=10029 gids={50029, 3003}
07-12 17:13:18.627: I/ActivityManager(432): Start proc com.andrew.apollo for broadcast com.andrew.apollo/.appwidgets.AppWidgetSmall: pid=6767 uid=10000 gids={50000, 1015, 3003, 1028}
07-12 17:13:18.901: I/ActivityManager(432): No longer want net.cactii.flash2 (pid 6395): empty #17
07-12 17:13:18.937: I/ActivityManager(432): Start proc com.google.android.gsf.login for service com.google.android.gsf.login/com.google.android.gsf.loginservice.GoogleLoginService: pid=6781 uid=10052 gids={50052, 3003, 1007, 1028, 1015, 1006, 3002, 3001, 2001, 3006}
07-12 17:13:18.947: V/KeyguardHostView(432): hide transport, gen:3
07-12 17:13:18.947: V/KeyguardHostView(432): music state changed: 0
07-12 17:13:19.117: D/PhoneStatusBar(583): disable: < EXPAND* icons alerts TICKER* system_info back home RECENT* clock search >
07-12 17:13:19.167: V/TAG(432): bug 7643792: fitSystemWindows([0,38][0,0])
07-12 17:13:19.214: D/PhoneStatusBar(583): disable: < EXPAND icons alerts TICKER system_info BACK* HOME* RECENT CLOCK* search >
07-12 17:13:19.377: I/ActivityManager(432): No longer want com.android.defcontainer (pid 6462): empty #17
07-12 17:13:19.674: I/ActivityManager(432): No longer want com.android.keychain (pid 6549): empty #17
07-12 17:13:23.678: W/ActivityManager(432): Activity stop timeout for ActivityRecord{420b2be8 u0 com.example.test/.MainActivity}
答案 0 :(得分：1)
如果字体是比例（变量字符长度），则需要进行迭代：
1. Start with length 1
2. Calculate the width using Paint object and setTypeFace, setTextSize methods
3. Increase length, check if it still fits, if not the result is (length -1)
这里代码的外观如何。您只需编写自己的方法，返回给定长度的数字作为字符串（请参阅下面的getNumberAsString）：
public int getLength(int fsize, Typeface tface, int field_width) {
int len = 1;
Paint paint = new Paint();
Rect rect = new Rect();
while (true) {
paint.setTypeface(tface);
paint.setTextSize(fsize);
String text = getNumberAsString(len);
paint.getTextBounds(text, 0, text.length(), rect);
if (rect.width() > field_width)
break;
len++;
}
return len - 1;
}
在您当前的实施中＆＃39;而＆＃39;循环永远不会结束，因为你不会改变＆＃39; string＆＃39;的大小。要解决此问题，您需要添加以下功能：
public String getNumberAsString(int len, String string) {
String numbersigns="0.";
for (int i =0; i<len;i++){
numbersigns=numbersigns+"#";
}
numbersigns=numbersigns+"E0";
NumberFormat formatter = new DecimalFormat(numbersigns);
return (formatter.format(Double.parseDouble(string)));
}
然后在你的＆＃39;中使用它。循环如下：
cur_str = getNumberAsString(len, string);
paint.getTextBounds(cur_str, 0, cur_str.length(), rect);
我还发现了一个非常好的解释，为什么setText（＆＃39;错误＆＃39;）之前调用了＆＃39;而＆＃39;循环没有工作。详细说明在下面的帖子中提供。 setText使视图无效。因此，视图最终将被重新绘制，但不会在当前方法完成之前重新绘制。由于你的方法是＆＃39;而且＆＃39;循环永远不会结束，视图永远不会被重新绘制。 Android TextView.setText() invoked & returned before Thread.sleep() blocks until sleep() returns. Why?