我的页面中有以下 Vuetify 布局:
<v-hover
v-for="(prop, index) in obj.props"
:key="prop"
v-slot:default="{ hover }">
<v-card flat tile
width="120"
class="mr-2 d-flex">
<v-text-field single-line flat dense required
v-model="obj.props[index]"
type="number"
label="Prop"
height="30" />
<v-fade-transition>
<v-btn text icon small
color="error"
class="customPropCardRemove mt-2"
:class="{ 'showCustomPropCardRemove': hover}"
@click="removeCustomProp(obj, index)">
<font-awesome-icon
color="error"
icon="times"
class="fa-sm" />
</v-btn>
</v-fade-transition>
</v-card>
</v-hover>
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基本上它是一个带有卡片内相邻按钮的文本字段。将鼠标悬停在卡片上时,按钮会淡入。那个有效。但是,文本字段在单次输入后失去焦点。
我想也许 v-hover/v-fade-transition 会以某种方式影响它,所以我试图将其删除并保持按钮始终可见:
<v-card flat tile
v-for="(prop, index) in obj.props"
:key="prop"
width="120"
class="mr-2 d-flex">
<v-text-field single-line flat dense required
v-model="obj.props[index]"
label="Prop"
height="30" />
<v-btn text icon small
color="error"
class="mt-2" …Run Code Online (Sandbox Code Playgroud) 我必须在随机生成的数字中找到最左边的数字(例如:46891 - > 4).无论数字是多少,我都会一直为零.这是我尝试的代码之一:
int num1 = (int)((Math.random()*100000)+1);
while((Math.floor(num1/10))>0)
{
num1 = (int)Math.floor(num1/10);
}
System.out.println("Left digit: " + num1);
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我试图使用Integer.parseInt,但显然我犯了这个错误:Integer类型中的方法parseInt(String)不适用于参数(int).
我做错了什么,我怎么能让它发挥作用?
谢谢!
我正在尝试从video画布上的元素中绘制视频.我写了以下JS代码:
$(function () {
var video = $("#video");
video.bind("loadedmetadata", function () {
var vw = this.videoWidth;
var vh = this.videoHeight;
var canvas = $('#canvas');
canvas.width(vw).height(vh);
var context = canvas.getContext("2d");
video.addEventListener("play", function () { draw(video, context, vw, vh); }, false);
});
});
function draw(video, context, vw, vh)
{
if (video.paused || video.ended)
{
return false;
}
context.drawImage(video, 0, 0, vw, vh);
setTimeout(draw, 20, video, context, vw, vh);
}
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这是我的HTML:
<body>
<video id="video" autoplay controls>
<source src="src1.avi" />
<source src="src2.mov" …Run Code Online (Sandbox Code Playgroud) 这是我的Activity XML的布局:

出于某种原因,我无法在屏幕底部看到该按钮.这是代码:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/app_bg"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/bg_transparent"
android:orientation="vertical"
android:minHeight="44dip"
android:minWidth="44dip" >
<TextView
android:id="@+id/lblNotesCount"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:textSize="18sp"
android:textStyle="bold"
android:textColor="@color/lblNotesCountColor" />
<TextView
android:id="@+id/lblTxtNotes"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:textSize="14sp"
android:textStyle="bold"
android:textColor="@color/lblNotesCountColor" />
</LinearLayout>
<TextView
android:id="@+id/txtActivityListByCategory_Header"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:ellipsize="end"
android:gravity="center_vertical|center_horizontal"
android:paddingLeft="2dp"
android:singleLine="true"
android:textStyle="bold"
android:textColor="@color/color_WHITE" />
<Button
android:id="@+id/btnAddNote"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/btn_new_note_selector"
android:minHeight="44dip"
android:minWidth="44dip" />
</LinearLayout>
<TextView
android:id="@+id/emptyList"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="2dp"
android:text="@string/txtEmptyList"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="@color/emptyList" />
<ListView
android:id="@+id/lstNotesByCategory"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawSelectorOnTop="false" …Run Code Online (Sandbox Code Playgroud)