[英]How to add image in a TextView text?
我在谷歌上搜索並發現了這個網站,在那里我發現了一個類似於我的問題,其中如何在TextView
文本中包含圖像,例如"hello my name is [image]" ,答案是這樣的:
ImageSpan is = new ImageSpan(context, resId);
text.setSpan(is, index, index + strLength, 0);
我想在這段代碼中知道,
text.setSpan()
做一些事情,比如導入或引用還是保留文本?如果有人可以為我分解這一點,我將不勝感激。
試試這個 ..
txtview.setCompoundDrawablesWithIntrinsicBounds(
R.drawable.image, 0, 0, 0);
也看到這個.. http://developer.android.com/reference/android/widget/TextView.html
在 xml 文件中試試這個
<TextView
android:id="@+id/txtStatus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:drawableLeft="@drawable/image"
android:drawablePadding="5dp"
android:maxLines="1"
android:text="@string/name"/>
com/xyz/customandroid/ TextViewWithImages .java :
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import android.content.Context;
import android.text.Spannable;
import android.text.style.ImageSpan;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.TextView;
public class TextViewWithImages extends TextView {
public TextViewWithImages(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public TextViewWithImages(Context context, AttributeSet attrs) {
super(context, attrs);
}
public TextViewWithImages(Context context) {
super(context);
}
@Override
public void setText(CharSequence text, BufferType type) {
Spannable s = getTextWithImages(getContext(), text);
super.setText(s, BufferType.SPANNABLE);
}
private static final Spannable.Factory spannableFactory = Spannable.Factory.getInstance();
private static boolean addImages(Context context, Spannable spannable) {
Pattern refImg = Pattern.compile("\\Q[img src=\\E([a-zA-Z0-9_]+?)\\Q/]\\E");
boolean hasChanges = false;
Matcher matcher = refImg.matcher(spannable);
while (matcher.find()) {
boolean set = true;
for (ImageSpan span : spannable.getSpans(matcher.start(), matcher.end(), ImageSpan.class)) {
if (spannable.getSpanStart(span) >= matcher.start()
&& spannable.getSpanEnd(span) <= matcher.end()
) {
spannable.removeSpan(span);
} else {
set = false;
break;
}
}
String resname = spannable.subSequence(matcher.start(1), matcher.end(1)).toString().trim();
int id = context.getResources().getIdentifier(resname, "drawable", context.getPackageName());
if (set) {
hasChanges = true;
spannable.setSpan( new ImageSpan(context, id),
matcher.start(),
matcher.end(),
Spannable.SPAN_EXCLUSIVE_EXCLUSIVE
);
}
}
return hasChanges;
}
private static Spannable getTextWithImages(Context context, CharSequence text) {
Spannable spannable = spannableFactory.newSpannable(text);
addImages(context, spannable);
return spannable;
}
}
采用:
在res/layout/mylayout.xml 中:
<com.xyz.customandroid.TextViewWithImages
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#FFFFFF00"
android:text="@string/can_try_again"
android:textSize="12dip"
style=...
/>
請注意,如果您將TextViewWithImages.java放置在com/xyz/customandroid/以外的某個位置,則還必須更改包名稱,即上面的com.xyz.customandroid
。
在res/values/strings.xml 中:
<string name="can_try_again">Press [img src=ok16/] to accept or [img src=retry16/] to retry</string>
其中ok16.png和retry16.png是res/drawable/文件夾中的圖標
我嘗試了許多不同的解決方案,這對我來說是最好的:
SpannableStringBuilder ssb = new SpannableStringBuilder(" Hello world!");
ssb.setSpan(new ImageSpan(context, R.drawable.image), 0, 1, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
tv_text.setText(ssb, TextView.BufferType.SPANNABLE);
此代碼使用最少的內存。
這個答案基於18446744073709551615 的這個優秀答案。 他們的解決方案雖然有用,但不會使用周圍的文本調整圖像圖標的大小。 它也不會將圖標顏色設置為周圍文本的顏色。
下面的解決方案采用一個白色的方形圖標,使其適合周圍文本的大小和顏色。
public class TextViewWithImages extends TextView {
private static final String DRAWABLE = "drawable";
/**
* Regex pattern that looks for embedded images of the format: [img src=imageName/]
*/
public static final String PATTERN = "\\Q[img src=\\E([a-zA-Z0-9_]+?)\\Q/]\\E";
public TextViewWithImages(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public TextViewWithImages(Context context, AttributeSet attrs) {
super(context, attrs);
}
public TextViewWithImages(Context context) {
super(context);
}
@Override
public void setText(CharSequence text, BufferType type) {
final Spannable spannable = getTextWithImages(getContext(), text, getLineHeight(), getCurrentTextColor());
super.setText(spannable, BufferType.SPANNABLE);
}
private static Spannable getTextWithImages(Context context, CharSequence text, int lineHeight, int colour) {
final Spannable spannable = Spannable.Factory.getInstance().newSpannable(text);
addImages(context, spannable, lineHeight, colour);
return spannable;
}
private static boolean addImages(Context context, Spannable spannable, int lineHeight, int colour) {
final Pattern refImg = Pattern.compile(PATTERN);
boolean hasChanges = false;
final Matcher matcher = refImg.matcher(spannable);
while (matcher.find()) {
boolean set = true;
for (ImageSpan span : spannable.getSpans(matcher.start(), matcher.end(), ImageSpan.class)) {
if (spannable.getSpanStart(span) >= matcher.start()
&& spannable.getSpanEnd(span) <= matcher.end()) {
spannable.removeSpan(span);
} else {
set = false;
break;
}
}
final String resName = spannable.subSequence(matcher.start(1), matcher.end(1)).toString().trim();
final int id = context.getResources().getIdentifier(resName, DRAWABLE, context.getPackageName());
if (set) {
hasChanges = true;
spannable.setSpan(makeImageSpan(context, id, lineHeight, colour),
matcher.start(),
matcher.end(),
Spannable.SPAN_EXCLUSIVE_EXCLUSIVE
);
}
}
return hasChanges;
}
/**
* Create an ImageSpan for the given icon drawable. This also sets the image size and colour.
* Works best with a white, square icon because of the colouring and resizing.
*
* @param context The Android Context.
* @param drawableResId A drawable resource Id.
* @param size The desired size (i.e. width and height) of the image icon in pixels.
* Use the lineHeight of the TextView to make the image inline with the
* surrounding text.
* @param colour The colour (careful: NOT a resource Id) to apply to the image.
* @return An ImageSpan, aligned with the bottom of the text.
*/
private static ImageSpan makeImageSpan(Context context, int drawableResId, int size, int colour) {
final Drawable drawable = context.getResources().getDrawable(drawableResId);
drawable.mutate();
drawable.setColorFilter(colour, PorterDuff.Mode.MULTIPLY);
drawable.setBounds(0, 0, size, size);
return new ImageSpan(drawable, ImageSpan.ALIGN_BOTTOM);
}
}
如何使用:
只需在文本中嵌入對所需圖標的引用。 文本是否通過textView.setText(R.string.string_resource);
編程方式設置textView.setText(R.string.string_resource);
或者如果它是在 xml 中設置的。
要嵌入名為 example.png 的可繪制圖標,請在文本中包含以下字符串: [img src=example/]
。
例如,字符串資源可能如下所示:
<string name="string_resource">This [img src=example/] is an icon.</string>
fun TextView.addImage(atText: String, @DrawableRes imgSrc: Int, imgWidth: Int, imgHeight: Int) {
val ssb = SpannableStringBuilder(this.text)
val drawable = ContextCompat.getDrawable(this.context, imgSrc) ?: return
drawable.mutate()
drawable.setBounds(0, 0,
imgWidth,
imgHeight)
val start = text.indexOf(atText)
ssb.setSpan(VerticalImageSpan(drawable), start, start + atText.length, Spannable.SPAN_INCLUSIVE_EXCLUSIVE)
this.setText(ssb, TextView.BufferType.SPANNABLE)
}
VerticalImageSpan
類來自很好的答案https://stackoverflow.com/a/38788432/5381331
使用
val textView = findViewById<TextView>(R.id.textview)
textView.setText("Send an [email-icon] to example@email.com.")
textView.addImage("[email-icon]", R.drawable.ic_email,
resources.getDimensionPixelOffset(R.dimen.dp_30),
resources.getDimensionPixelOffset(R.dimen.dp_30))
結果
筆記
為什么是VerticalImageSpan
類?
ImageSpan.ALIGN_CENTER
屬性需要 API 29。
另外,經過測試,我看到ImageSpan.ALIGN_CENTER
僅在圖像小於文本時才起作用,如果圖像大於文本,則只有圖像在中心,文本不在中心,它在圖像底部對齊
這部分基於@A Boschman 上面的早期答案。 在該解決方案中,我發現圖像的輸入大小極大地影響了makeImageSpan()
正確居中對齊圖像的能力。 此外,我發現該解決方案通過創建不必要的行間距影響了文本間距。
我發現BaseImageSpan (來自 Facebook 的 Fresco 庫)可以很好地完成這項工作:
/**
* Create an ImageSpan for the given icon drawable. This also sets the image size. Works best
* with a square icon because of the sizing
*
* @param context The Android Context.
* @param drawableResId A drawable resource Id.
* @param size The desired size (i.e. width and height) of the image icon in pixels.
* Use the lineHeight of the TextView to make the image inline with the
* surrounding text.
* @return An ImageSpan, aligned with the bottom of the text.
*/
private static BetterImageSpan makeImageSpan(Context context, int drawableResId, int size) {
final Drawable drawable = context.getResources().getDrawable(drawableResId);
drawable.mutate();
drawable.setBounds(0, 0, size, size);
return new BetterImageSpan(drawable, BetterImageSpan.ALIGN_CENTER);
}
然后像往常一樣將您的 betterImageSpan 實例提供給spannable.setSpan()
這可能對你有幫助
SpannableStringBuilder ssBuilder;
ssBuilder = new SpannableStringBuilder(" ");
// working code ImageSpan image = new ImageSpan(textView.getContext(), R.drawable.image);
Drawable image = ContextCompat.getDrawable(textView.getContext(), R.drawable.image);
float scale = textView.getContext().getResources().getDisplayMetrics().density;
int width = (int) (12 * scale + 0.5f);
int height = (int) (18 * scale + 0.5f);
image.setBounds(0, 0, width, height);
ImageSpan imageSpan = new ImageSpan(image, ImageSpan.ALIGN_BASELINE);
ssBuilder.setSpan(
imageSpan, // Span to add
0, // Start of the span (inclusive)
1, // End of the span (exclusive)
Spanned.SPAN_INCLUSIVE_EXCLUSIVE);// Do not extend the span when text add later
ssBuilder.append(" " + text);
ssBuilder = new SpannableStringBuilder(text);
textView.setText(ssBuilder);
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