在Android开发中如果出现android.content.res.Resources$NotFoundException: String resource ID #0x1这样的错误，你想也不用想，一定是Textview控件显示数据出了问题：mTextview.setText(这里的传入的数据一定写成int类型了)。我们需要做的是eg:mTextview.setText(1+""),也就是参数转化成字符串，接下来我们看一源码：
如果控件TextView添加的数据写成 eg：mTextview.setText(1)时，也就是传入的是数字，源码分析如下：
/**
* Sets the text to be displayed using a string resource identifier.
*
* @param resid the resource identifier of the string resource to be displayed
*
* @see #setText(CharSequence)
*
* @attr ref android.R.styleable#TextView_text
*/
@android.view.RemotableViewMethod
public final void setText(@StringRes int resid) {
setText(getContext().getResources().getText(resid));
mTextFromResource = true;
}
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从该方法的注释我们可以看到参数 resid要是一个string的类型。接着我们往下看getText():
/**
* Return the string value associated with a particular resource ID. The
* returned object will be a String if this is a plain string; it will be
* some other type of CharSequence if it is styled.
* {@more}
*
* @param id The desired resource identifier, as generated by the aapt
* tool. This integer encodes the package, type, and resource
* entry. The value 0 is an invalid identifier.
*
* @throws NotFoundException Throws NotFoundException if the given ID does not exist.
*
* @return CharSequence The string data associated with the resource, plus
* possibly styled text information.
*/
@NonNull public CharSequence getText(@StringRes int id) throws NotFoundException {
CharSequence res = mResourcesImpl.getAssets().getResourceText(id);
if (res != null) {
return res;
}
throw new NotFoundException("String resource ID #0x"
+ Integer.toHexString(id));
}
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上面的意思大概是：返回与特定资源ID相关联的字符串值。返回的对象将是一个字符串，如果这是一个普通的字符串;@param id ：所需的资源标识符,由aapt工具生成。这个整数编码了包、类型和资源条目，值0是无效标识符。接着继续往下看类AssetManager：
/**
* Retrieves the string value associated with a particular resource
* identifier for the current configuration.
*检索与特定资源相关联的字符串值当前配置的标识符。
* @param resId the resource identifier to load
* @return the string value, or {@code null}
*/
@Nullable
final CharSequence getResourceText(@StringRes int resId) {
synchronized (this) {
final TypedValue outValue = mValue;
if (getResourceValue(resId, 0, outValue, true)) {
return outValue.coerceToString();
}
return null;
}
}
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返回字符序列CharSequence。那么是如何 检索与特定资源相关联的字符串 值。
继续看源码：
/**
* Populates {@code outValue} with the data associated a particular
* resource identifier for the current configuration.
*
* @param resId the resource identifier to load
* @param densityDpi the density bucket for which to load the resource
* @param outValue the typed value in which to put the data
* @param resolveRefs {@code true} to resolve references, {@code false}
* to leave them unresolved
* @return {@code true} if the data was loaded into {@code outValue},
* {@code false} otherwise
*/
final boolean getResourceValue(@AnyRes int resId, int densityDpi, @NonNull TypedValue outValue,
boolean resolveRefs) {
synchronized (this) {
final int block = loadResourceValue(resId, (short) densityDpi, outValue, resolveRefs);
if (block < 0) {
return false;
}
// Convert the changing configurations flags populated by native code.
outValue.changingConfigurations = ActivityInfo.activityInfoConfigNativeToJava(
outValue.changingConfigurations);
if (outValue.type == TypedValue.TYPE_STRING) {
outValue.string = mStringBlocks[block].get(outValue.data);
}
return true;
}
}
/** Returns true if the resource was found, filling in mRetStringBlock and
* mRetData. */
private native final int loadResourceValue(int ident, short density, TypedValue outValue,
boolean resolve);
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如果找到对应的资源，则返回true。在这里我们也看到了native方法，
肯定是c/c++去做事了，我们不去考虑。如果找不到返回null,
我们从如下代码就可以知道：
@Nullable
final CharSequence getResourceText(@StringRes int resId) {
synchronized (this) {
final TypedValue outValue = mValue;
if (getResourceValue(resId, 0, outValue, true)) {
return outValue.coerceToString();
}
return null;
}
}
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如果找到对应的资源，我们就经过一系列的方法转化成字符序列，
代码如下：
/**
* Regardless of the actual type of the value,
try to convert it to a
* string value. For example, a color type will be converted
to a
* string of the form #aarrggbb.
*
* @return CharSequence The coerced string value.
If the value is
* null or the type is not known, null is returned.
*/
public final CharSequence coerceToString()
{
int t = type;
if (t == TYPE_STRING) {
return string;
}
return coerceToString(t, data);
}
2.------------------------------------------/**
* Perform type conversion as per {@link #coerceToString()} on an
* explicitly supplied type and data.
*
* @param type The data type identifier.
* @param data The data value.
*
* @return String The coerced string value. If the value is
* null or the type is not known, null is returned.
*/
public static final String coerceToString(int type, int data)
{
switch (type) {
case TYPE_NULL:
return null;
case TYPE_REFERENCE:
return "@" + data;
case TYPE_ATTRIBUTE:
return "?" + data;
case TYPE_FLOAT:
return Float.toString(Float.intBitsToFloat(data));
case TYPE_DIMENSION:
return Float.toString(complexToFloat(data)) + DIMENSION_UNIT_STRS[
(data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK];
case TYPE_FRACTION:
return Float.toString(complexToFloat(data)*100) + FRACTION_UNIT_STRS[
(data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK];
case TYPE_INT_HEX:
return "0x" + Integer.toHexString(data);
case TYPE_INT_BOOLEAN:
return data != 0 ? "true" : "false";
}
if (type >= TYPE_FIRST_COLOR_INT && type <= TYPE_LAST_COLOR_INT) {
return "#" + Integer.toHexString(data);
} else if (type >= TYPE_FIRST_INT && type <= TYPE_LAST_INT) {
return Integer.toString(data);
}
return null;
}
........................... |
如果控件TextView添加的数据写成 eg：mTextview.setText(1+"")时，也就是传入的是字符串，源码分析如下：
next1.
/**
* Sets the text to be displayed. TextView <em>does not</em> accept
* HTML-like formatting, which you can do with text strings in XML resource files.
* To style your strings, attach android.text.style.* objects to a
* {@link android.text.SpannableString}, or see the
* <a href="{@docRoot}guide/topics/resources/available-resources.html#stringresources">
* Available Resource Types</a> documentation for an example of setting
* formatted text in the XML resource file.
* <p/>
* When required, TextView will use {@link android.text.Spannable.Factory} to create final or
* intermediate {@link Spannable Spannables}. Likewise it will use
* {@link android.text.Editable.Factory} to create final or intermediate
* {@link Editable Editables}.
*
* @param text text to be displayed
*
* @attr ref android.R.styleable#TextView_text
*/
@android.view.RemotableViewMethod
public final void setText(CharSequence text) {
setText(text, mBufferType);
}
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next2.
设置要显示的文本
/**
* Sets the text to be displayed and the {@link android.widget.TextView.BufferType}.
* <p/>
* When required, TextView will use {@link android.text.Spannable.Factory} to create final or
* intermediate {@link Spannable Spannables}. Likewise it will use
* {@link android.text.Editable.Factory} to create final or intermediate
* {@link Editable Editables}.
*
* @param text text to be displayed
* @param type a {@link android.widget.TextView.BufferType} which defines whether the text is
* stored as a static text, styleable/spannable text, or editable text
*
* @see #setText(CharSequence)
* @see android.widget.TextView.BufferType
* @see #setSpannableFactory(Spannable.Factory)
* @see #setEditableFactory(Editable.Factory)
*
* @attr ref android.R.styleable#TextView_text
* @attr ref android.R.styleable#TextView_bufferType
*/
public void setText(CharSequence text, BufferType type) {
setText(text, type, true, 0);
if (mCharWrapper != null) {
mCharWrapper.mChars = null;
}
}
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next3.
private void setText(CharSequence text, BufferType type,
boolean notifyBefore, int oldlen) {
mTextFromResource = false;
if (text == null) {
text = "";
}
// If suggestions are not enabled, remove the suggestion spans from the text
if (!isSuggestionsEnabled()) {
text = removeSuggestionSpans(text);
}
............ ................. .........
notifyViewAccessibilityStateChangedIfNeeded(AccessibilityEvent.CONTENT_CHANGE_TYPE_TEXT);
if (needEditableForNotification) {
sendAfterTextChanged((Editable) text);
} else {
// Always notify AutoFillManager - it will return right away if autofill is disabled.
notifyAutoFillManagerAfterTextChangedIfNeeded();
}
// SelectionModifierCursorController depends on textCanBeSelected, which depends on text
if (mEditor != null) mEditor.prepareCursorControllers();
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