Question

我的应用正常呈现，但为什么change事件函数updateItem(item)无法触发？

模板：

  <ion-list>
    <ion-item-sliding *ngFor="#item of items">
      <ion-item>
        <ion-label>{{item.title}}</ion-label>
        <ion-toggle [(ngModel)]="item.completed" (change)="updateItem(item)"></ion-toggle>
      </ion-item>
      <ion-item-options>
        <button primary (click)="editItem(item)">
          <ion-icon name="edit"></ion-icon>Edit
        </button>
      <button secondary (click)="deleteItem(item)">
        <ion-icon name="delete"></ion-icon>Delete
      </button>
      </ion-item-options>
    </ion-item-sliding>
  </ion-list>

类别：

export class Todos {
...
  updateItem(item) {
    alert(1)
    this._todosService.update(item).subscribe(
      response => { this.getItems(); }
    );
  }
... 
}

Answer 1

根据the Ionic documentation，您可以这样做：

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
import matplotlib.colors as colors
import matplotlib.cm as cmx

# from apodemus's Stackoverflow answer,
# https://stackoverflow.com/questions/18602660/matplotlib-bar3d-clipping-problems
def sph2cart(r, theta, phi):
    '''spherical to Cartesian transformation.'''
    x = r * np.sin(theta) * np.cos(phi)
    y = r * np.sin(theta) * np.sin(phi)
    z = r * np.cos(theta)
    return x, y, z

def sphview(ax):
    '''returns the camera position for 3D axes in spherical coordinates'''
    r = np.square(np.max([ax.get_xlim(), ax.get_ylim()], 1)).sum()
    theta, phi = np.radians((90-ax.elev, ax.azim))
    return r, theta, phi
#
# end of apodemus's code

def getDistances(view):
    distances  = []
    a = np.array((xpos, ypos, dz))
    for i in range(len(xpos)):
        distance = (a[0, i] - view[0])**2 + (a[1, i] - view[1])**2 + (a[2, i] - view[2])**2
        distances.append(np.sqrt(distance))
    return distances

# ================================================================

# my data
dat = [2.31778665482167e-310, 0.006232785101850947, 0.0285075971030949, 0.0010248181570355695, 0.0048776795767614825, 0.02877090365176044, 0.002459331469834533, 0.0008594610645495889, 0.002919824084878003, 0.000968081117692596, 0.0, 0.0, 0.0319623949119874, 0.00568752311279771, 0.009994801469036968, 0.03248018520506219, 0.006686905726805326, 0.005987863156039365, 0.0072955095915350045, 0.005568911905473998, 0.0, 0.0, 0.0, 0.028483143996551524, 0.031030793902192794, 0.06125216053962635, 0.02935971973938871, 0.028507530280092265, 0.030112963748812088, 0.028293406731749605, 0.0, 0.0, 0.0, 0.0, 0.004510645022825792, 0.028998119822468988, 0.0013993630391143715, 0.0010726572949244424, 0.002288215944285159, 0.0006513973584945584, 0.0, 1.1625e-320, 1.15348834e-316, 2.3177866547513e-310, 0.0, 0.03148966953869102, 0.005215047563268979, 0.004491716298086729, 0.006010166308872446, 0.005186976949223524, 0.0, 0.0, 0.0, 0.0, 0.0, 1.107e-320, 0.02983657915729719, 0.028893006725328373, 0.030526067389954753, 0.028629390713739978, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0015217840289869456, 0.002751587509779179, 0.001413669523724954, 1.15348834e-316, 2.3177866547513e-310, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0024680339073824705, 0.0008254364860386303, 0.0, 0.0, 0.0, 9.965e-321, 1.15348834e-316, 2.3177866547513e-310, 0.0, 0.0, 0.0, 0.002621588539481613, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 9.41e-321, 1.15348834e-316, 2.3177866547513e-310]
dat = np.reshape(dat,[10,10],order='F')

lx = len(dat[0])
ly = len(dat[:,0])
n = lx*ly

# generate colors
cm = plt.get_cmap('jet')
vv = range(len(dat))
cNorm = colors.Normalize(vmin=0, vmax=vv[-1])
scalarMap = cmx.ScalarMappable(norm=cNorm, cmap=cm)
colorVals = [scalarMap.to_rgba(i) for i in range(ly)]

# generate plot data
xpos = np.arange(0,lx,1)  
ypos = np.arange(0,ly,1)
xpos, ypos = np.meshgrid(xpos+0.25, ypos+0.25)
xpos = xpos.flatten()
ypos = ypos.flatten()
zpos = np.zeros(n)
dx = 0.5*np.ones_like(zpos)
dy = dx.copy()
dz = dat.flatten()
cc = np.tile(range(lx), (ly,1))
cc = cc.T.flatten()

# generate plot
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
opacity = 1

# Get the camera's location in Cartesian coordinates.
x1, y1, z1 = sph2cart(*sphview(ax))
camera = np.array((x1,y1,0))
# Calculate the distance of each bar from the camera.
z_order = getDistances(camera)
max = max(z_order)

for i in range(n):
    pl = ax.bar3d(xpos[i], ypos[i], zpos[i], dx[i], dy[i], dz[i],
             color=colorVals[cc[i]], alpha=opacity, zsort='max')
    # The z-order must be set explicitly.
    #
    # z-order values are somewhat backwards in magnitude, in that the largest
    # value is closest to the camera - unlike, in say, a coordinate system.
    # Therefore, subtracting the maximum distance from the calculated distance
    # inverts the z-order to the proper form.
    pl._sort_zpos = max - z_order[i]

plt.autoscale(enable=True, axis='both', tight=True)
plt.grid()
plt.show()

我希望这会对你有所帮助！

Answer 2

<强>更新

<ion-toggle [(ngModel)]="itemCompleted"></ion-toggle>

export class Todos {
  get itemCompleted() {
    return item.completed;
  }
  set itemCompleted(value) {
    item.completed = value;
    updateItem(item);
  }

  ...
  updateItem(item) {
    alert(1)
    this._todosService.update(item).subscribe(
      response => { this.getItems(); }
    );
  }
  ... 
}

<强>原始

当[(ngModel)]="..."有效时，

(ngModelChange)="updateItem(item)"

应该也可以，也可以做你想要完成的事情。

Answer 3

如果初始值为true，则ionChange无用，因为它每次都触发。

<ion-toggle [(ngModel)]="item.completed" (ngModelChange)="updateItem(item)"></ion-toggle>

希望这有用！

Ionic2切换组件更改事件未触发

3 个答案: